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Q2) A relay coil has a resistance of 200 Ω and the current required to operate the relay is 150 mA.

When the coil is connected to a 50 V d.c. supply it takes 40 ms for the relay to operate.

(a) Calculate EACH of the following:

(i) the steady state relay current; (2)

(ii) the time constant for the coil; (4)

(iii) the inductance of the coil. (4)

(b) To increase the operating time for the relay, a 50 Ω resistor is connected in series with the coil.

Determine the new operating time for the relay. (6)