A ball of clay of mass m is thrown with a speed v against a brick wall. The clay sticks to the wall and stops. Is the principle of conservation of momentum violated in this example?

Momentum is not conserved.

Explanation:

Given that

mass of clay = m

initial velocity = v

We know that linear momentum P = m v

Initial momentum Pi = m v

The final velocity of clay and wall = 0

That is why final momentum = 0

Therefore here momentum is not conserved.

So we can say that linear momentum is not conserve.

Actually when clay strike to the wall then after wall and clay move with some speed but this speed is very very small and we can not detect it.