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Hi guys, ive got this tutorial sheet to do, and im pretty stuck on it, i don't really need the answers i can do them myself i just need somewhere to start on the questions and and idea of what to do. Help much appreciated!

1. A car starts from rest and moves along a straight road with acceleration 9ms-2. After 5 seconds another car starts from rest at the same point and moves along the same road with acceleration 16ms-2.

• How long after the first car starts will the second car catch it up?

• What are the velocities of the two cars when they first meet?

• The second car now stops accelerating and travels at constant velocity. How many more seconds after the first meeting will they meet again?

2. Particle A of mass 2 kg and particle B of mass 5 kg are connected by a light inextensible string, which passes over a smooth fixed pulley at the top of a smooth plane inclined at 30° to the horizontal. A is on the plane and B is hanging vertically. At t = 0 both particles are moving with speed 4ms-1 with A moving downwards and B moving upwards and A is 1 m from the top of the plane.

• Calculate when A reaches the top of the plane.

3. A constant horizontal force of 30 N is applied to a particle of mass 5 kg which moves up a smooth plane inclined at 20° to the horizontal. The particle is initially at rest. Find the velocity and the work done by the force after t seconds.

4. Particle A has mass 5kg and particle B has mass 1kg. They lie on a smooth horizontal surface and the line joining them is normal to a vertical wall with B closer to the wall. The coefficient of restitution between the two particles is Ep = 0.8 and the coefficient of restitution between B and the wall is Ew = 0.5. Initially A is at rest and B is moving towards A at a speed of 2m/s. B collides first with A and then with the wall.

• Will it collide with A again?

• What is the final velocity of A?

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# Homework Help: Mechanics Help Needed

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