Suppose we have a situation like
A ball of some mass $m$ with some velocity collides with rod hinged at point $A$.
Is momentum conserved in this situation? I know that hinge will give impulsive force on rod but that is internal force when we take ball and rod together as a system so that shouldn't stop us using conservation of momentum equation
Best Answer
Generally speaking linear momentum cannot be conserved in this case as hinge will exert a (external) force on rod at all but one position.
Note:Angular momentum is definitely conserved about hinged point since the force applied by hinge produces zero torque here.
Solving we get $d=\dfrac{2l}{3}$