Question

Why is it easier to turn the steering wheel of a car if it's diameter is large ?

Answer 1

the torque is larger for large diameter steering. Hence, it is easier to turn the steering wheel of large diameter than the steering wheel of small diameter with the same applied force. so It is easier to turn the steering wheel of a larger diameter than that of a smaller diameter.

Answer 2

The larger the radius the greater the torque. Another way of stating that is that a smaller force on a large wheel could generate the same torque as greater force on a smaller wheel. Hence, the steering wheel of heavy vehicles has large diameter.