Correct Answer - Option 4 : 1500 N

__Concept:__

The Effective turning or driving force at the circumference of the driven pulley = (T1 - T2)

Where,

T_{1} = Tension in the tight side in Newtons.

T_{2} = Tension in the slack side in Newtons.

__Calculation:__

__Given:__

T_{1} = 3000 N, T_{2} = 1500 N

The Effective turning force at the circumference of the driven pulley = (T1 - T2) = (3000 - 1500) = **1500 N**