7th Class Science Related to Competitive Exam Question Bank

done Work and energy Total Questions - 102

• question_answer1)
  Work done = Force\[\times \] ...........
  A)
  Displacement               done clear
  B)
  Speed done clear
  C)
           Velocity                        done clear
  D)
  Acceleration done clear
  View Solution play_arrow

• question_answer2)
  \[1joule=1\]...............
  A)
   \[N{{m}^{2}}\]                               done clear
  B)
   \[kg\,m/{{s}^{2}}\] done clear
  C)
   \[1Nm\]                       done clear
  D)
   \[{{N}^{2}}{{m}^{2}}\] done clear
  View Solution play_arrow

• question_answer3)
  A force of 20 Newton s is pushing an object 5 Meters in the direction of the force. How much work is done?
  A)
  4 J                               done clear
  B)
  25 J done clear
  C)
  15 J                             done clear
  D)
  100 J done clear
  View Solution play_arrow

• question_answer4)
  Which of the following statements is not correct?
  A)
  Energy is capacity to do work done clear
  B)
  Work can be expressed as force\[\times \]displacement done clear
  C)
  Unit of work done is joule done clear
  D)
  Unit of energy is Newton done clear
  View Solution play_arrow

• question_answer5)
  The sum of potential energy and kinetic energy is
  A)
  Electrical energy           done clear
  B)
  Mechanical energy done clear
  C)
  Chemical energy          done clear
  D)
  Heat energy done clear
  View Solution play_arrow

• question_answer6)
  Ability to do work is..........
  A)
  Force                           done clear
  B)
  displacement done clear
  C)
  Energy             done clear
  D)
  Velocity done clear
  View Solution play_arrow

• question_answer7)
  The C.G.S. unit of work is
  A)
  Dyne                done clear
  B)
  erg done clear
  C)
  Newton                        done clear
  D)
  Joule done clear
  View Solution play_arrow

• question_answer8)
  Work is a form of..........
  A)
  Force              done clear
  B)
  displacement done clear
  C)
  Energy            done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer9)
  \[1\text{joule=}\].......... ergs
  A)
   \[{{10}^{7}}\]              done clear
  B)
   \[\text{1}{{0}^{\text{5}}}\] done clear
  C)
   \[\text{1}{{0}^{\text{4}}}\]                                    done clear
  D)
   \[\text{1}{{0}^{\text{9}}}\] done clear
  View Solution play_arrow

• question_answer10)
  Energy which creates a sensation of vision is
  A)
  light energy      done clear
  B)
  heat energy done clear
  C)
  chemical energy           done clear
  D)
  potential energy done clear
  View Solution play_arrow

• question_answer11)
  A form of energy which is caused by vibrations is
  A)
  heat energy                  done clear
  B)
  sound energy done clear
  C)
  light energy                  done clear
  D)
  chemical energy done clear
  View Solution play_arrow

• question_answer12)
  Chemical energy is converted into electrical energy by
  A)
  battery done clear
  B)
  washing machine done clear
  C)
  fen                               done clear
  D)
  Refrigerator done clear
  View Solution play_arrow

• question_answer13)
  Chemical energy is converted into heat energy by
  A)
  bulb                done clear
  B)
  electric geyser done clear
  C)
  electric motor               done clear
  D)
  burning of fuel done clear
  View Solution play_arrow

• question_answer14)
  Washing machine converts energy
  A)
  electrical energy to chemical energy done clear
  B)
  electrical energy to mechanical energy done clear
  C)
  chemical energy to sound energy done clear
  D)
  mechanical energy to electrical energy done clear
  View Solution play_arrow

• question_answer15)
  Heat energy is caused by difference in
  A)
  force               done clear
  B)
  work done clear
  C)
  temperature       done clear
  D)
  Velocity done clear
  View Solution play_arrow

• question_answer16)
  Water stored in the water tank at the roof of house has
  A)
  kinetic energy   done clear
  B)
  potential energy done clear
  C)
  chemical energy           done clear
  D)
  light energy done clear
  View Solution play_arrow

• question_answer17)
  Kinetic energy possessed by a body of mass 3 kg moving at speed of3m/sec is
  A)
  13.6 J              done clear
  B)
  27 J done clear
  C)
  4.5 J                            done clear
  D)
  54 J done clear
  View Solution play_arrow

• question_answer18)
  .................. produces sound energy using electrical energy
  A)
  electric bell     done clear
  B)
  battery done clear
  C)
  refrigerator                   done clear
  D)
  electric bulb done clear
  View Solution play_arrow

• question_answer19)
  Electric oven converts
  A)
  chemical energy into heat energy done clear
  B)
  heat energy into chemical energy done clear
  C)
  heat energy into electrical energy done clear
  D)
  electric energy into heat energy done clear
  View Solution play_arrow

• question_answer20)
  A child pushes a car but it does not displace from its place then, the work done will be known as
  A)
  positive work               done clear
  B)
  negative work done clear
  C)
  zero work          done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer21)
  Identify the kind of energy possessed by a running athlete.
  A)
  potential energy           done clear
  B)
  kinetic energy done clear
  C)
  electrical energy           done clear
  D)
  sound energy done clear
  View Solution play_arrow

• question_answer22)
  When a body falls, then its total energy. [Hint: Consider the law of conservation of energy]
  A)
  increases done clear
  B)
  first increases then decreases done clear
  C)
  decreases done clear
  D)
  remains constant done clear
  View Solution play_arrow

• question_answer23)
  The S.I. unit of energy is
  A)
  joule                 done clear
  B)
  dyne done clear
  C)
  erg                               done clear
  D)
  Newton done clear
  View Solution play_arrow

• question_answer24)
  Work can never be
  A)
  negative                      done clear
  B)
  positive done clear
  C)
  zero                  done clear
  D)
  none of these done clear
  View Solution play_arrow

• question_answer25)
  Kinetic energy and potential energy are types of .........energy.
  A)
  Nuclear                        done clear
  B)
  mechanical done clear
  C)
  Heat               done clear
  D)
  Sound done clear
  View Solution play_arrow

• question_answer26)
  According to the definition of work, when a boy sits on a place and study for the whole night, he does
  A)
  very little work              done clear
  B)
  lot of work done clear
  C)
  no work            done clear
  D)
  cannot say done clear
  View Solution play_arrow

• question_answer27)
  The...............is the main source of energy on the planet earth.
  A)
  moon               done clear
  B)
  wind done clear
  C)
  sun                   done clear
  D)
  Fire done clear
  View Solution play_arrow

• question_answer28)
  Newton meter is the S.I. unit of
  A)
  work             done clear
  B)
  force done clear
  C)
  pressure                       done clear
  D)
  Acceleration done clear
  View Solution play_arrow

• question_answer29)
  Negative value of work done indicates that
  A)
  Force and displacement are in the same direction done clear
  B)
  More than one force is acting on the object done clear
  C)
  Displacement and force are in opposite directions done clear
  D)
  Both (b) and (c) done clear
  View Solution play_arrow

• question_answer30)
  Capacity of doing work is termed as
  A)
  Pressure           done clear
  B)
  Energy done clear
  C)
  Force                           done clear
  D)
  Displacement done clear
  View Solution play_arrow

• question_answer31)
  A fast wind can turn the blades of a windmill because it possesses -
  A)
  potential energy           done clear
  B)
  kinetic energy done clear
  C)
  chemical energy           done clear
  D)
  heat energy done clear
  View Solution play_arrow

• question_answer32)
  The sum of the change in kinetic and potential energy is always
  A)
  zero          done clear
  B)
  positive done clear
  C)
  negative           done clear
  D)
  None of the above done clear
  View Solution play_arrow

• question_answer33)
  DIRECTION: Match column-I with Column-II and select the correct answer using the code given below the columns. Column I shows some devices and column II shows transformation of energy for which they are used.

  Column-I	Column-II
  (A) Electric motor	(p) Electrical energy to heat energy
  (B) Automobile engine	(q) Electrical energy to mechanical energy
  (C) Electric heater	(r) Light energy to electrical energy
  (D) Photocell	(s) Heat energy to mechanical energy

  A)
  A\[\to \] (q), B\[\to \] (s), C\[\to \] (p), D\[\to \] (r) done clear
  B)
  A\[\to \] (r), B\[\to \] (p), C\[\to \] (s), D\[\to \] (q) done clear
  C)
  A\[\to \] (p), B\[\to \] (q), C\[\to \] (r), D\[\to \] (s) done clear
  D)
  A\[\to \] (s), B\[\to \] (r), C\[\to \] (q), D\[\to \] (p) done clear
  View Solution play_arrow

• question_answer34)
  DIRECTION: Match column-I with Column-II and select the correct answer using the code given below the columns.

  Column-I	Column-II
  (A) Work	(p) \[\frac{1}{2}m{{v}^{2}}\]
  (B) Energy	(q) vibrations
  (C) Kinetic energy	(r) can be positive, negative or zero
  (D) Sound energy	(s) ability to do work

  A)
  A\[\to \] (q), B\[\to \] (s), C\[\to \] (p), D\[\to \] (r) done clear
  B)
  A\[\to \] (s), B\[\to \] (r), C\[\to \] (q), D\[\to \] (p) done clear
  C)
  A\[\to \] (r), B\[\to \] (s), C\[\to \] (p), D\[\to \] (q) done clear
  D)
  A\[\to \] (r), B\[\to \] (s), C\[\to \] (q), D\[\to \] (p) done clear
  View Solution play_arrow

• question_answer35)
  DIRECTION: Match column-I with Column-II and select the correct answer using the code given below the columns.

  Column-I	Column-II
  (A) Potential energy	(p) mgh
  (B) Work	(q) can never be created or destroyed
  (C) 1 joule	(r) \[\text{f }\!\!\times\!\!\text{ d}\]
  (D) Energy	(s) \[\text{1}{{\text{0}}^{\text{7}}}\]erg

  A)
  A\[\to \] (r), B\[\to \] (s), C\[\to \] (p), D\[\to \] (q) done clear
  B)
  A\[\to \] (p), B\[\to \] (r), C\[\to \] (q), D\[\to \] (s) done clear
  C)
  A\[\to \] (q), B\[\to \] (s), C\[\to \] (p), D\[\to \] (r) done clear
  D)
  A\[\to \] (p), B\[\to \] (r), C\[\to \] (s), D\[\to \] (q) done clear
  View Solution play_arrow

• question_answer36)
  DIRECTIONS: Read the passage given below and answer the questions that follow. Passage Rishabh, a professional skateboarder, is taking part in a skateboarding competition. Rishabh waits at the top of the ramp before skateboarding down it. Different points on the ramp are marked A, B, C and D. At which point. A, B, C or D, does Rishabh has the most gravitational potential energy?
  A)
  A           done clear
  B)
  B done clear
  C)
  C                                 done clear
  D)
  D done clear
  View Solution play_arrow

• question_answer37)
  DIRECTIONS: Read the passage given below and answer the questions that follow. Passage Rishabh, a professional skateboarder, is taking part in a skateboarding competition. Rishabh waits at the top of the ramp before skateboarding down it. Different points on the ramp are marked A, B, C and D. At which point on the ramp will Rishabh nor has any kinetic energy?
  A)
  A               done clear
  B)
  B done clear
  C)
  C                                 done clear
  D)
  D done clear
  View Solution play_arrow

• question_answer38)
  DIRECTIONS: Read the passage given below and answer the questions that follow. Passage Rishabh, a professional skateboarder, is taking part in a skateboarding competition. Rishabh waits at the top of the ramp before skateboarding down it. Different points on the ramp are marked A, B, C and D. At which point, Rishabh has both kinetic and potential energy simultaneously?
  A)
  A                                  done clear
  B)
  B done clear
  C)
  C                                 done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer39)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as "Assertion A" and the other labeled as "Reason R". You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of I the assertion. Select your answers to these items using codes given below. Assertion (A): A coolie having a heavy box on his head is standing at a fixed place, he is not doing any work. Reason (R): Work is said to be done only when there is displacement.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer40)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as "Assertion A" and the other labeled as "Reason R". You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of I the assertion. Select your answers to these items using codes given below. Assertion (A): When a body is displaced from its initial position, then in such a situation work is always done by the force applied on the body Reason (R): Work = force\[\times \]displacement
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer41)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as "Assertion A" and the other labeled as "Reason R". You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of I the assertion. Select your answers to these items using codes given below. Assertion (A): We can see objects in sunlight only. Reason (R): Sunlight causes a sensation of vision.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer42)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as "Assertion A" and the other labeled as "Reason R". You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of I the assertion. Select your answers to these items using codes given below. Assertion (A): Electric geyser is used to heat water. Reason (R): Electric geyser converts electric energy into heat energy.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer43)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as "Assertion A" and the other labeled as "Reason R". You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of I the assertion. Select your answers to these items using codes given below. Assertion (A): Sound energy can be produced by electric bell. Reason (R): Electric bell is a device which is used to convert electric energy into sound energy.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer44)
  DIRECTIONS: Read the following two statements carefully and choose the correct options. Statement 1: Work is always done when a body is in accelerated motion under a force acting on the body. Statement 2: Work depends only on force which is the product of mass and acceleration.
  A)
  Statement (1) is correct while statement (2) is incorrect. done clear
  B)
  Statement (2) is correct while statement (1) is incorrect. done clear
  C)
  Both statements are correct done clear
  D)
  Both statements are incorrect. done clear
  View Solution play_arrow

• question_answer45)
  DIRECTIONS: Read the following two statements carefully and choose the correct options. Statement 1: Work done on a toy car moving forward is positive. Statement 2: It gets displace in the direction of applied force.
  A)
  Statement (1) is correct while statement (2) is incorrect. done clear
  B)
  Statement (2) is correct while statement (1) is incorrect. done clear
  C)
  Both statements are correct done clear
  D)
  Both statements are incorrect. done clear
  View Solution play_arrow

• question_answer46)
  DIRECTIONS: Read the following two statements carefully and choose the correct options. Statement 1: Falling water has only kinetic energy. Statement 2: Kinetic energy is possessed by objects in motion.
  A)
  Statement (1) is correct while statement (2) is incorrect. done clear
  B)
  Statement (2) is correct while statement (1) is incorrect. done clear
  C)
  Both statements are correct done clear
  D)
  Both statements are incorrect. done clear
  View Solution play_arrow

• question_answer47)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: The girl in the picture above is using a long bar to lift a heavy box. Using the bar makes the girl's task easier by
  A)
  reducing the input force done clear
  B)
  reducing the box's mass done clear
  C)
  increasing the amount of work done done clear
  D)
  increasing the distance the box is lifted done clear
  View Solution play_arrow

• question_answer48)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: Three objects having same mass are placed as shown in figure. Which will have the maximum potential energy?
  A)
  A done clear
  B)
  B done clear
  C)
  C done clear
  D)
  All three have same energy done clear
  View Solution play_arrow

• question_answer49)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: In many parts of the world, strong winds cause a lot of destruction. Which of the following forms? Of energy in the winds cause(s) the destruction? A. Heat energy             B. Light energy C. Kinetic energy         D. Potential energy
  A)
  A only                          done clear
  B)
  C only done clear
  C)
  A, B and D only           done clear
  D)
  A and B only done clear
  View Solution play_arrow

• question_answer50)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: Study the diagram below. At which position does the ball have the most kinetic energy?
  A)
  A                                  done clear
  B)
  B done clear
  C)
  C                                 done clear
  D)
  D done clear
  View Solution play_arrow

• question_answer51)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: The diagram below shows two children playing on a see-saw. What is the energy conversion that takes place when two children are playing on a see-saw?
  A)
  kinetic energy\[\to \]heat energy\[\to \] gravitational potential energy done clear
  B)
  chemical potential energy\[\to \]kinetic energy\[\to \]gravitational potential energy done clear
  C)
  gravitational potential energy\[\to \]kinetic energy\[\to \]chemical potential energy done clear
  D)
  gravitational potential energy\[\to \]kinetic energy\[\to \]gravitational potential energy done clear
  View Solution play_arrow

• question_answer52)
  A man pushes a wall and fails to displace it He does
  A)
  negative work done clear
  B)
  positive but not maximum work            ' done clear
  C)
  no work at all done clear
  D)
  maximum work done clear
  View Solution play_arrow

• question_answer53)
  If force and displacement of particle in direction of force are doubled. Work would be
  A)
  double                          done clear
  B)
  4 times done clear
  C)
  half                              done clear
  D)
  1/4times done clear
  View Solution play_arrow

• question_answer54)
  Two bodies of masses 2kg and 5kg respectively are moving at same velocity. The ratio of their kinetic energy is
  A)
  2:5              done clear
  B)
  7:5 done clear
  C)
  4:25                             done clear
  D)
  25:4 done clear
  View Solution play_arrow

• question_answer55)
  According to the law of conservation of energy
  A)
  energy can be created or destroyed done clear
  B)
  energy can never be created or destroyed done clear
  C)
  cannot be transformed from one form to another form done clear
  D)
  Both (b) and (c) done clear
  View Solution play_arrow

• question_answer56)
  A carton is pulled along the ground for a distance of 5 m. If the force of friction is 79 N, then the work done is
  A)
  79 J                             done clear
  B)
  5 J done clear
  C)
  16 J                             done clear
  D)
  395 J done clear
  View Solution play_arrow

• question_answer57)
  A cat of mass 8 kg is running after a rat with a uniform acceleration of 1m/sec2. After running 40 m it gets success to catch the rat. The work done by the cat in the process is
  A)
  320 J         done clear
  B)
  640 J done clear
  C)
  5 J                               done clear
  D)
  10 J done clear
  View Solution play_arrow

• question_answer58)
  Potential energy of your body is minimum when you
  A)
  are standing done clear
  B)
  are sitting on a chair done clear
  C)
  are sitting on the ground done clear
  D)
  lie down on the ground done clear
  View Solution play_arrow

• question_answer59)
  Water stored in a dam possess
  A)
  no energy                     done clear
  B)
  electrical energy done clear
  C)
  potential energy           done clear
  D)
  kinetic energy done clear
  View Solution play_arrow

• question_answer60)
  Kinetic energy possessed by a car, moving at a speed of 5 m/sec is 5000 J. The mass of the car is
  A)
  400kg               done clear
  B)
  1250kg done clear
  C)
  200kg               done clear
  D)
  2500kg done clear
  View Solution play_arrow

• question_answer61)
  An object P of mass 2 kg is moving at 10m/sec and object Q of mass 3 kg is moving at 7 m/sec. Which object will possess more K.E.?
  A)
  Object P done clear
  B)
  Object Q done clear
  C)
  Both objects will possess same energy done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer62)
  A man holding a suitcase of mass 15 kg and was waiting for a bus from past 15 minutes. Then the work done is
  A)
  Positive                        done clear
  B)
  Negative done clear
  C)
  Zero                done clear
  D)
  15joule done clear
  View Solution play_arrow

• question_answer63)
  The potential energy associated with an object of mass 6 kg placed at a height 12 m from the ground is \[(g=10m/{{s}^{2}})\]
  A)
  7.2 J                            done clear
  B)
  72 J done clear
  C)
  7200 J             done clear
  D)
  720 J done clear
  View Solution play_arrow

• question_answer64)
  Aman throws a ball with a force of 20N.Findthe distance covered by the ball if work done is 60 J in this process.
  A)
  3m     done clear
  B)
  9m done clear
  C)
  6m                               done clear
  D)
  12m done clear
  View Solution play_arrow

• question_answer65)
  Ravi pushes a rock with a force of 10 N for 5 minutes but it remains as it is. The work done by him is
  A)
  positive                        done clear
  B)
  negative done clear
  C)
  zero              done clear
  D)
  none of these done clear
  View Solution play_arrow

• question_answer66)
  Same amount of work has to be done on two objects A and B of same mass by applying force of 8 N and 16 N respectively. Then A will displace
  A)
  more than object B      done clear
  B)
  less than object B done clear
  C)
  Same as B                   done clear
  D)
  Cannot say done clear
  View Solution play_arrow

• question_answer67)
  A boy pushes a toy cart along a level road and then lets it go. As the cart is slowing down, the biggest energy change is from
  A)
  Heat to kinetic             done clear
  B)
  Kinetic to heat done clear
  C)
  Kinetic to potential       done clear
  D)
  Potential to heat done clear
  View Solution play_arrow

• question_answer68)
  For a body falling freely under gravity from a height
  A)
  only the potential energy goes on increasing done clear
  B)
  only the kinetic energy goes on increasing done clear
  C)
  both kinetic energy as well as potential energy go on increasing done clear
  D)
  the kinetic energy goes on increasing while potential energy goes on decreasing done clear
  View Solution play_arrow

• question_answer69)
  Kinetic energy of a body moving with speed 10 m/s is 30J. If its speed becomes 30 m/s, its kinetic energy will be
  A)
  10 J                             done clear
  B)
  90 J done clear
  C)
  180 J                           done clear
  D)
  270 J done clear
  View Solution play_arrow

• question_answer70)
  No work is done when
  A)
  a nail is plugged into a wooden board done clear
  B)
  a box is pushed along a horizontal floor done clear
  C)
  there is no component of force parallel to the direction of motion done clear
  D)
  there is no component of force normal to the direction of force done clear
  View Solution play_arrow

• question_answer71)
  Work done by a force can be
  A)
  only positive done clear
  B)
  only negative done clear
  C)
  both positive and negative done clear
  D)
  None of these done clear
  View Solution play_arrow

• question_answer72)
  What is the sign of the work done by gravity on a man standing on a platform?
  A)
  Zero done clear
  B)
  Positive done clear
  C)
  Negative done clear
  D)
  Depends on the particular situation done clear
  View Solution play_arrow

• question_answer73)
  A bird flying in the sky has -
  A)
  K.E. only done clear
  B)
  P.E. only done clear
  C)
  neither K.E. nor P.E. done clear
  D)
  both K.E. and P.E. done clear
  View Solution play_arrow

• question_answer74)
  Sun is said to be the ultimate source of energy. Solar energy gets transformed into
  A)
  chemical energy during photosynthesis done clear
  B)
  heat energy in drying food grains done clear
  C)
  electrical energy in solar cells done clear
  D)
  All of these done clear
  View Solution play_arrow

• question_answer75)
  The potential energy of a freely falling object decreases progressively.
  A)
  The law of conservation of energy is violated done clear
  B)
  Potential energy gets converted into kinetic energy progressively done clear
  C)
  Sum of Potential Energy and Kinetic Energy at any point during the free fall remains constant done clear
  D)
  Both (b) and (c) done clear
  View Solution play_arrow

• question_answer76)
  DIRECTION: Match Column-I with Column-II and select the correct answer using the code given below the columns.  

  Column - I	Column - II
  (A) Electric iron	(p) Electrical energy to light energy
  (B) Washing machine	(q) Electrical energy to heat energy
  (C) Solar cell	(r) Electrical energy to mechanical energy
  (D) CFL	(s) Light energy to electrical energy

  A)
  A\[\to \] (r), B\[\to \] (s), C\[\to \] (p), D\[\to \] (r) done clear
  B)
  A\[\to \] (p), B\[\to \] (r), C\[\to \] (s), D\[\to \] (q) done clear
  C)
  A\[\to \] (q), B\[\to \] (r), C\[\to \] (s), D\[\to \] (p) done clear
  D)
  A\[\to \] (q), B\[\to \] (s), C\[\to \] (p), D\[\to \] (r) done clear
  View Solution play_arrow

• question_answer77)
  DIRECTION: Match Column-I with Column-II and select the correct answer using the code given below the columns.

  Column - I	Column - II
  (A) a car is moving in the direction of force	(p) zero work
  (B) A boy is studying in his classroom	(q) negative work
  (C) Rising up of an object against force of gravity	(r) Potential energy
  (D) Water stored in tank on the roof	(s) Positive work

  A)
  A\[\to \] (s), B\[\to \] (p), C\[\to \] (q), D\[\to \] (r) done clear
  B)
  A\[\to \] (r), B\[\to \] (s), C\[\to \] (q), D\[\to \] (p) done clear
  C)
  A\[\to \] (p), B\[\to \] (r), C\[\to \] (s), D\[\to \] (q) done clear
  D)
  A\[\to \] (q), B\[\to \] (p), C\[\to \] (r), D\[\to \] (s) done clear
  View Solution play_arrow

• question_answer78)
  DIRECTION: Match Column-I with Column-II and select the correct answer using the code given below the columns.  

  Column - I	Column - II
  (A) Energy due to motion	(p) Potential energy
  (B) Energy due to position	(q) Kinetic energy
  (C) Energy stored in battery	(r) Chemical energy
  (D) Energy between two charge particles at rest	(s) Electrostatic energy

  A)
  A\[\to \] (q), B\[\to \] (p), C\[\to \] (s), D\[\to \] (r) done clear
  B)
  A\[\to \] (q), B\[\to \] (p), C\[\to \] (r), D\[\to \] (s) done clear
  C)
  A\[\to \] (p), B\[\to \] (q), C\[\to \] (r), D\[\to \] (s) done clear
  D)
  A\[\to \] (q), B\[\to \] (r), C\[\to \] (p), D\[\to \] (s) done clear
  View Solution play_arrow

• question_answer79)
  DIRECTIONS: Read the passage (s) given below and answer the questions that follow. Passage ? 1 Centripetal force is a requirement for circular motion.  No work is done on a body by centripetal force in a circular path. The work done by a centripetal force -
  A)
  increases by decreasing the radius of the circle done clear
  B)
  decreases by increasing the radius of the circle done clear
  C)
  increases by increasing the mass of the body done clear
  D)
  is always zero done clear
  View Solution play_arrow

• question_answer80)
  DIRECTIONS: Read the passage (s) given below and answer the questions that follow. Passage ? 1 Centripetal force is a requirement for circular motion.  No work is done on a body by centripetal force in a circular path. The moon revolves around the earth because the earth exerts a radial force on the moon. Does the earth perform work on the moon?
  A)
  No done clear
  B)
  Yes, sometimes done clear
  C)
  Yes, always done clear
  D)
  Cannot be decided done clear
  View Solution play_arrow

• question_answer81)
  DIRECTIONS: Read the passage (s) given below and answer the questions that follow. Passage ? 2 The picture below shows four newly-manufactured, identical cars being transported to a car showroom. Based on your observations, answer questions 30 and 31. Which of the cars has/have the highest potential energy?
  A)
  Car P only done clear
  B)
  Cars P and Q only done clear
  C)
  Cars R and S only done clear
  D)
  All the cars have equal potential energy done clear
  View Solution play_arrow

• question_answer82)
  DIRECTIONS: Read the passage (s) given below and answer the questions that follow. Passage ? 2 The picture below shows four newly-manufactured, identical cars being transported to a car showroom. Based on your observations, answer questions 30 and 31. Which of the following is true about the kinetic energy of the four cars?
  A)
  None of the cars have kinetic energy done clear
  B)
           All the cars have equal kinetic energy done clear
  C)
           Cars P and Q have more kinetic energy than cars R and S. done clear
  D)
  Cars Q and Shave more kinetic energy than cars P and R. done clear
  View Solution play_arrow

• question_answer83)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as ?Assertion A? and the other labeled as ?Reason R?. You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of the assertion. Select your answers to these items using codes given below Assertion (A): A moving hammer drives a nail into wood. Reason (R): A moving hammer has potential energy.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer84)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as ?Assertion A? and the other labeled as ?Reason R?. You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of the assertion. Select your answers to these items using codes given below Assertion (A): The driver increases the speed of his car on approaching a hilly road. Reason (R): To give more kinetic energy to the car so that it may go up against gravity.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer85)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as ?Assertion A? and the other labeled as ?Reason R?. You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of the assertion. Select your answers to these items using codes given below Assertion (A): Winding up the spring of a toy car gives it energy for moving. Reason (R): Work done in winding the spring gets stored up as kinetic energy.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer86)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as ?Assertion A? and the other labeled as ?Reason R?. You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of the assertion. Select your answers to these items using codes given below Assertion (A): A person walking on horizontal road with a load on his head does no work. Reason (R): No work is said to be done, if the directions of force and displacement of load are perpendicular to each other.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer87)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as ?Assertion A? and the other labeled as ?Reason R?. You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of the assertion. Select your answers to these items using codes given below Assertion (A): When a gas is allowed to expand, work done by gas is positive. Reason (R): Force due to gaseous pressure and displacement (of piston) are in the same direction.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer88)
  DIRECTIONS: The questions in this segment consist of two statements, one labeled as ?Assertion A? and the other labeled as ?Reason R?. You are to examine these two statements carefully and decide if the Assertion A and Reason R are individually true and if so, whether the reason is a correct explanation of the assertion. Select your answers to these items using codes given below Assertion (A): Wire through which current flows gets heated. Reason (R): When current is drawn from a cell, chemical energy is converted into heat energy.
  A)
  Both A and R are true and R is the correct explanation of A. done clear
  B)
  Both A and R are true but R is not the correct explanation of A. done clear
  C)
  A is true but R is false. done clear
  D)
  A is false but R is true. done clear
  View Solution play_arrow

• question_answer89)
  DIRECTIONS: Read the following three statements carefully and choose the correct option. Statement 1: A man gets completely exhausted in trying to push a stationary wall. The work done by him is zero. Statement 2: Work done is the product of force and displacement. Statement 3: Work can be positive, negative and zero.
  A)
  Statement (1) and (3) are incorrect while statement (2) is correct. done clear
  B)
  Statement (1) and (2) are incorrect while (3) is correct. done clear
  C)
  All the statements are correct. done clear
  D)
  All the statements are incorrect. done clear
  View Solution play_arrow

• question_answer90)
  DIRECTIONS: Read the following three statements carefully and choose the correct option. Statement 1: A car engine converts heat energy into chemical energy. Statement 2: A car bums fuel to get energy. Statement 3: Car engine can produce heat energy from other sources like water also.
  A)
  Statement (1) and (3) are incorrect while statement (2) is correct. done clear
  B)
  Statement (1) and (2) are incorrect while (3) is correct. done clear
  C)
  All the statements are correct. done clear
  D)
  All the statements are incorrect. done clear
  View Solution play_arrow

• question_answer91)
  DIRECTIONS: Read the following three statements carefully and choose the correct option. Statement 1: Kinetic energy of a body is quadrupled, when its velocity is doubled. Statement 2: Kinetic energy is proportional to square of velocity. Statement 3: Kinetic energy is the energy of body due to its motion.
  A)
  Statement (1) and (3) are incorrect while statement (2) is correct. done clear
  B)
  Statement (1) and (2) are incorrect while (3) is correct. done clear
  C)
  All the statements are correct. done clear
  D)
  All the statements are incorrect. done clear
  View Solution play_arrow

• question_answer92)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: A mass M is hung from a spring. It is then pulled down slightly and allowed to vibrate vertically between P and Q. Which row is correct?

  	Energy at point P	Energy at point Q
  A	kinetic	kinetic
  B	kinetic	potential
  C	potential	kinetic
  D	potential	potential

  A)
  A                                  done clear
  B)
  B done clear
  C)
  C                                 done clear
  D)
  D done clear
  View Solution play_arrow

• question_answer93)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: A mass hangs on a string fixed at point P. It starts from position 1 and swings to the farthest position on the opposite side, position 2. It then oscillates several times with decreasing amplitude before ending at position 3. Where does the ball have the most kinetic energy?
  A)
  at position 1 done clear
  B)
  at position 2 done clear
  C)
  the first time at position 3 done clear
  D)
  the last time at position 3 done clear
  View Solution play_arrow

• question_answer94)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: A man, carrying a bag of sand, is walking at a constant speed. There is a hole in the bag and sand is continuously falling out. His kinetic energy at point B will be ________ his kinetic energy at point A.
  A)
  less than           done clear
  B)
  more than done clear
  C)
  equal to            done clear
  D)
  zero, equal to done clear
  View Solution play_arrow

• question_answer95)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: The flowchart below shows the conversion of electricity to other forms of energy by three electrical appliances. Which of the options below best represents the forms of the energy produced by the appliances? A          B                      C                    D
  A)
  Heat                Light                Kinetic             Sound done clear
  B)
  Kinetic             Heat                Sound              Light done clear
  C)
  Kinetic             Sound              Light                Heat done clear
  D)
  Sound              Kinetic             Heat                Light done clear
  View Solution play_arrow

• question_answer96)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: A small wooden box of mass 1 kg is placed on a big wooden box of mass 2 kg. The big box is moving on a smooth surface with a constant. Velocity 2 m/sec. The K.E. possessed by this system is (Assume there is no frictional force between the surfaces)
  A)
  4J                                done clear
  B)
  8J done clear
  C)
  6J                    done clear
  D)
  12J done clear
  View Solution play_arrow

• question_answer97)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: A car and a bike are moving with same velocity on two different roads as shown below. If their K.E. are 100 J and 80 J respectively, then, the ratio of their respective masses is
  A)
  4:5                               done clear
  B)
  5:4 done clear
  C)
  2:5                               done clear
  D)
  4:10 done clear
  View Solution play_arrow

• question_answer98)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: Which one is used to convert electric energy to mechanical energy?
  A)
  done clear
  B)
  done clear
  C)
             done clear
  D)
  done clear
  View Solution play_arrow

• question_answer99)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: Two objects displaced as shown in figure after applying same amount of force. The work done will be
  A)
  greater in condition 1 done clear
  B)
  greater in condition 2 done clear
  C)
  same in condition 1 and 2 done clear
  D)
  cannot say done clear
  View Solution play_arrow

• question_answer100)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: Two objects, a chalk box of mass 0.5 kg and a ball of mass 0.8 kg are placed at same height h as shown in figure. Then the potential energy is
  A)
  greater for chalk box done clear
  B)
  greater for ball done clear
  C)
  same for both chalk box and ball done clear
  D)
  cannot say done clear
  View Solution play_arrow

• question_answer101)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: Rima's bicycle has a dynamo (a small electrical generator) and a lamp. As she pedals, the dynamo spins and her lamp lights up, helping her to see at night. Which of the following correctly shows the energy conversions that occur?
  A)
  Electrical energy \[\to \] kinetic energy + light energy + heat energy done clear
  B)
  Kinetic energy \[\to \] chemical potential energy \[\to \] light energy done clear
  C)
  Kinetic energy \[\to \] electrical energy \[\to \] light energy + heat energy done clear
  D)
  Chemical potential energy \[\to \] electrical energy\[\to \]light energy done clear
  View Solution play_arrow

• question_answer102)
  DIRECTIONS: On the basis of following diagram/ picture answer the questions given below: The toy cars shown below are of the same size and are moving at the same speed. However, they do not have the same amount of kinetic energy because________.
  A)
  they are equal in mass done clear
  B)
  they are losing kinetic energy done clear
  C)
  they are made of different materials done clear
  D)
  they do not have any stored energy done clear
  View Solution play_arrow