2. Questions Bank
  3. JEE Main & Advanced
  4. Physics
  5. Electro Magnetic Induction

JEE Main & Advanced Physics Electro Magnetic Induction Question Bank Faraday's and Lenz's Law

  • question_answer
    A coil has 2000 turns and area of\[70c{{m}^{2}}\]. The magnetic field perpendicular to the plane of the coil is \[0.3Wb/{{m}^{2}}\]and takes 0.1sec to rotate through\[{{180}^{o}}\]. The value of the induced e.m.f. will be                        [MP PET 1993; Similar to AIIMS 1997]

    A)            \[8.4V\]                                  

    B)            \[84V\]

    C)            \[42V\]                                   

    D)            \[4.2V\]

    Correct Answer: B

    Solution :

                       \[e=-\frac{NBA(\cos {{\theta }_{2}}-\cos {{\theta }_{1}})}{\Delta t}\]                    \[=-2000\times 0.3\times 70\times {{10}^{-4}}\frac{(\cos 180-\cos 0)}{0.1}\]            \[\Rightarrow e=84\ V\]


You need to login to perform this action.
You will be redirected in 3 sec spinner