Q.

Assertion: Rolling without slipping cannot possible in absence of friction.

Reason: During rolling without slipping, energy can remain conserved in absence of external applied force.

1 Assertion is True, Reason is True, Reason is correct explanation for Assertion  
2 Assertion is True, Reason is True, Reason is NOT a correct explanation for Assertion  
3 Assertion is True, Reason is false  
4 Assertion is False, Reason is True  

Ans.

(4)

In uniform pure rolling, the linear velocity is constant. If no external force or torque is applied, the body will remain in a state of uniform pure rolling. In this case, the friction force is always zero, so there will not be any effect of the frictional force on the body.