2. Questions Bank
  3. 12th Class
  4. Physics
  5. Electrostatics & Capacitance

12th Class Physics Electrostatics & Capacitance Question Bank Case Based (MCQs) - Electrostatic Potential and Capacitance

  • question_answer
    A parallel plate capacitor of capacitance 1pF has separation between the plates is (d) When the distance of separation becomes 2d and wax of dielectric constant x is inserted in it the capacitance becomes 2 pF. What is the value of x?

    A) 2                     

    B) 4          

    C) 6                     

    D) 8

    Correct Answer: B

    Solution :

    (b) 4 \[C=\frac{{{\varepsilon }_{0}}A}{d}=1pF\]                                                                                                                    … (1) \[C'=\frac{x{{\varepsilon }_{0}}A}{\left( 2d \right)}=2pF\]                                                                                                                        … (2) Dividing eq. (2) by eq. (1), \[\frac{x}{2}=\frac{2}{1}\Rightarrow x=4\]


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