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(C) The back $EMF$ equation for a $DC$ motor is given by $E_b = V - I_a R_a$,where $V$ is the supply voltage,$I_a$ is the armature current,and $R_a$ i

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Motor has just started moving

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(C) The back $EMF$ equation for a $DC$ motor is given by $E_b = V - I_a R_a$,where $V$ is the supply voltage,$I_a$ is the armature current,and $R_a$ is the armature resistance.Rearranging for current,we get $I_a = \frac{V - E_b}{R_a}$.At the moment of starting,the motor speed is zero,which means the back $EMF$ $(E_b)$ is also zero.Therefore,at starting,$I_a = \frac{V}{R_a}$,which is the maximum possible value for the armature current.

Armature current in a $DC$ motor will be maximum when:

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