Question

A 33.0-V battery with negligible internal resistance, a 49.0-Ω resistor, and a 1.25-mH inductor with negligible resistance are all connected in series with an open switch. The switch is suddenly closed. How long after closing the switch will the energy stored in the inductor reach one-half of its maximum value?

Answer 1

Time constant 1.25x10 49 = 2.55 x 10° s Maximum energy: Half of its maximum value. U 1 2 12 ー- The time taken to reach the I value is same as that of energy to become half of its maximum value. e τ = 0.2928 = 1.2282 ち=3.13×10-5 s