Question

A charge 1/9 nC is uniformly distributed over a thin rod AB of length 1 m. As shown in the figure. The electric potential at point O lying at distance 2 m from end A is

Answer 1

Given:

A charge 1/9 nC is uniformly distributed over a thin rod AB of length 1 m. As shown in the figure.  

To find:

The electric potential at point O lying at distance 2 m from end A is

Solution:

From given, we have,

A charge 1/9 n C is uniformly distributed over a thin rod AB of length 1 m.

Q = 1/9 n C

L = 1 m

we use the direct formula for calculating the electric potential at a point and is given by,

V = Qln2/4π∈₀L

V = [(1/9) ln 2] / [4π∈₀ × 1]

we know, 1/4π∈₀ 9 × 10⁹

V = 9 × 10⁹ × [(1/9) ln 2]

V = 10⁹ × ln 2

V = 10⁹ × 0.6931

∴ The electric potential at point O lying at distance 2 m from end A is 0.6931 × 10⁹ V