From a point charge, there is a fixed point A. At A, there is an electric field of 500 V/m and potential difference of 3000 V. Distance between point charge and A will be ?

From a point charge, there is a fixed point A.  At A, there is an electric field of 500 V/m and potential difference of 3000 V. Distance between point charge and A  will be ?

(a) \( 6 \, \text{m} \)

(b) \( 12 \, \text{m} \)

(c) \( 16 \, \text{m} \)

(d) \( 24 \, \text{m} \)

Answer :  (a) \( 6 \, \text{m} \)

\( \text{Point charge} \) , \( E = \frac{kq}{d^2} = 500 \)

\( V = \frac{kq}{d} = 3000 \)

\( \frac{(1)}{(2)} \Rightarrow \frac{1}{d} = \frac{500}{3000} \)

\( d = 6 \, \text{m} \)

Alternate method \( \; ( \text{This is not point charge formula.} ) \)

\( E = \frac{V}{l} \)

\( 500 = \frac{3000}{l} \Rightarrow l = 6 \, \text{m} \)