# A sphere A, of mass 3 kg, is moving on a smooth horizontal floor with speed 4 ms–1 in a direction which is at right-angles to a smooth vertical wall. The sphere strikes the wall and rebounds with...

A sphere *A, *of mass 3 kg, is moving on a smooth horizontal floor with speed 4 ms–1 in a direction which is at right-angles to a smooth vertical wall. The sphere strikes the wall and rebounds with a speed of 2·8 ms–1.

Determine the magnitude of the impulse exerted by the wall on the sphere during the impact.

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The sphere with mass 3 kg, is initially moving on a smooth horizontal floor with speed 4 m/s. in a direction which is at right-angles to a smooth vertical wall. It sphere strikes the wall and rebounds with a speed of 2.8 m/s

The impulse on the ball by the wall is equal to the change in momentum of the ball. The initial momentum is 3*4 = 12 kg*m/s. And the momentum of the ball after it strikes the wall is -2.8*3 = -8.4. The change in momentum is 20.4

**The impulse produced by the wall is equal to 20.4 kg*m/s**