Question

A charge of 70 A ·h (ampere-hours) moves through a poten- difference of 25 V. What are (a) the charge in coulombs and（b) the magnitude of the change in the potential energy of the charge?

Answer 1

Answer

Given,

Charge, q = 70 A.h

Potential difference, V = 25 V

a) Charge, q = ?

we know that

  q= I t

    = 70 A.h

    = 70 x 60 x 60 A.s

    = 252,000 C

b) Potential energy of the charge

      U = q V

      U =  252,000 x 25

      U = 6,300,000 J