Answer:
V = 0.556V
Explanation:
In magnetic induction
Emf = [tex]\frac{L dI}{dt}[/tex]
This emf is equivalent to voltage applied:
[tex]V = \frac{L dI}{dt}[/tex]
Change in current is 150 - 0 = 150A
change in time is 180min = 180 * 60 = 10800seconds.
Thus,
[tex]V = \frac{40 * 150}{10800} \\V = \frac{6000}{10800}\\ V = 0.556V[/tex]