A 220V de shunt motor takes 22A at rated voltage and run at speed of 1,000 rpm. Its field resistance is 100 ohm and armature resistance is 0.1 ohm. Compute the value of additional resistance required in armature circuit to reduce the speed to 800 rpm when (i) load torque is proportional to speed and (ii) when load torque varies as the square of the speed. (10)