τ = L

R

Solution(a) L τ = R 10 = 60 = 0.17 seconds(b)the time it will take to reach its final value is five time constants (5 τ) 5 x 0.17 = 0.85 seconds

(c)the approximate final magnitude of current after 0.85 seconds can be calculated using ohmʼs law:

V I = R 120 = 60 = 2 A

63% of the difference between the maximum voltage and the current

voltage.

Maximum Circuit Current = 10 amps

Current = 63.2% = 6.32 ampsMax Voltage = 10 amps

10 - 6.32 = 3.68

The difference is 3.68 amps

63.2% of 3.68 = 2.32 amps

6.32 + 2.32 = 8.64 amps