Given:
Current: I = 5 A
Time: t = 4 min = 4 × 60 = 240 s
(a) Total charge (Q) in coulombs:
Q = I × t
= 5 × 240
= 1200 C
(b) Number of electrons:
Charge of one electron: e = 1.6 × 10^-19 C
Number of electrons = Q / e
= 1200 / (1.6 × 10^-19)
= 7.5 × 10^21 electrons
Answer:
(a) Q = 1200 C
(b) Number of electrons = 7.5 × 10^21