Question

The absolute potential at a distance of 2.0 m from a negative point charge is-100. V. What is the absolute potential 4.0 m away from the same point charge? A)-50. V B) -25. V C)-0.40 kV D)-020 kV E)-0.50 kV

Answer 1

Answer:

The absolute potential 4.0 m away from the same point charge is -50 V.

(A) is correct option.

Explanation:

Given that,

Distance = 2.0 m

Potential = -100 V

Absolute potential = 4.0 m

We need to calculate the charge

Using formula of potential

$V=\dfrac{kq}{r}$

Where, V = potential

q = charge

r = distance

Put the value into the formula

$-100=\dfrac{9\times10^{9}\times q}{2.0}$

$q=\dfrac{200}{9\times10^{9}}$

$q=-22.2\times10^{-9}\ C$

We need to calculate the potential

Using formula of potential

$V=\dfrac{9\times10^{9}\times(-22.2\times10^{-9})}{4.0}$

$V=-49.95\ V$

$V=-50\ V$

Hence, The absolute potential 4.0 m away from the same point charge is -50 V.