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Q1. When connected to a 20 V d.c. supply a relay starts to operate 0.52 ms after switching on the supply, at which time the instantaneous current is 200 mA. The relay coil has a time constant of 5 ms. (a) Calculate EACH of the following: 1. The final steady state relay current; 2. The resistance and inductance of the relay coil. (b) To increase the operating time a 40 Q resistor is connected in series with the relay coil.  Calculate the new time delay assuming the instantaneous current is 200 mA.