In actual machine, the rotor bars are embedded in the iron, hence the rotor circuit has leakage reactance. Thus the rotor current in each bar lags behind the generated e.m.f in that bar by rotor power factor angle:

(6)

From Figure 4 it is seen that bars a and b under the poles have a maximum generated e.m.fs. On account of the rotor reactance (x₂), the currents in these bars will be maximum only when the poles N₁ ,S₁ have traveled through an angle θ₂ (Figure 4). The rotor current generates rotor mmf F₂ is space displaced from the air gap flux Φ_m by a load angle . The torque produced by the motor in this situation is

(7)

Greater the value of x₂, greater is the departure of load angle from its optimal value of and lesser is the torque. To generate a high starting torque, θ₂ should be made as small as possible and this is done by increasing rotor resistance r₂.