A coil of inductance 40 H is connected in series with a resistance 8 Ω across a 2 V DC supply. What is its time constant?
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A coil of inductance 40 H is connected in series with a resistance 8 Ω across a 2 V DC supply. What is its time constant?

G1 Physics · Accepted Answer

Step 1: After DC supply connection an RL series circuit approaches its steady-state current exponentially. Step 2: Current-growth time constant is τ=L/R. Step 3: Given L=40H and R=8Ω, τ=40/8=5s. Correct A. Final answer: (A) 5 s.