Question

If the plates of a parallel plate capacitor connected to a battery are moved close to each other, then 

A. the charge stored in it, increases. 

B. the energy stored in it, decreases. 

C. its capacitance increases. 

D. the ratio of charge to its potential remains the same. 

E. the product of charge and voltage increases. 

Choose the most appropriate answer from the options given below: 

(1) A, B and E only 

(2) A, C and E only 

(3) B, D and E only 

(4) A, B and C only

Answer 1

Correct option is : (2) A, C and E only 

Battery connected so V = constant 

Now \( d\downarrow\, \Rightarrow C\uparrow\)   

\(A:Q = CV \propto C\Rightarrow Q \uparrow\)

\(B:U = \frac{1}{2}CV^2 \propto\ C \Rightarrow\ U \uparrow\) 

\(C:C = \ \frac{\in_0\ A}{d}\Rightarrow C\uparrow\) 

\(D : \frac{Q}{V} = C\Rightarrow C\uparrow\) 

\(E : (Q)\ (V)\propto C\Rightarrow QV\uparrow\)

Therefore statements A, C and E are correct.