A battery with emf e m f is connected in series with an inductance L and a resistance R. (a) Assuming the current has reached steady state when it is at 99% of its maximum value, how long does it take to reach steady state, assuming the initial current is zero? (Use any variable or symbol stated above as necessary. To represent e m f, use E.) t99% = (b) If an emergency power circuit needs to reach steady state within 1.2 ms of turning on and the circuit has a total resistance of 72 Ω, what values of the total inductance of the circuit are needed to satisfy the requirement? (Give the maximum value.) H

a)

b)

Explanation:

The current flowing in a R-L series circuit is given by

Where τ is the time constant and is given by

Where L is the inductance and R is the resistance

Assuming the current has reached steady state when it is at 99% of its maximum value,

Therefore, it would take t = 4.6τ to reach the steady state.

(b) If an emergency power circuit needs to reach steady state within 1.2 ms of turning on and the circuit has a total resistance of 72 Ω, what values of the total inductance of the circuit are needed to satisfy the requirement?

Therefore, an inductance of 0.0187 H is needed to satisfy the requirement.

where’s the list ? the question is incomplete