Question

An electron moves from point P at potential 30V to point Q such that work done is 1.6*10^-18.Find the potential at point Q

Answer 1

W = q∆V
W(given) = 1.6*10^-18
∆Vpq = (Vp - Vq) = (30- Vq)
1.6*10^-18 = e(30-Vq)
1.6*10^-18/e = (30-Vq)
-1= 30- Vq
Vq = 31 V

Answer 2

Given:

The potential at point P Vp= 30 V

The work done is W= 1.6×10⁻¹⁸

To find:

The potential at point Q.

Solution:

The formula of work done

The change of potential energy

W= Vp - Vq

1.6×10⁻¹⁸=30 - Vq

Vq= 30- 0.016

Vq=29.984 eV

So the potential at point Q in the form of electron volt is Vq=29.984 eV