PHYSICS Unit 3 MEC REVISION LECTURE

byGurwinder Singh,

Parkwood Sec College

Motion in one and two dimensions

The following diagram shows a car rolling down a slope. The car has a mass of 1.2  103 kg and the slope is at 15 to the horizontal. The acceleration due to gravity is 10 m s2.

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On the diagram mark in the forces acting on the car.

If the total resistance force acting on the car has a magnitude of 1000 N, calculate the acceleration of the car.

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The component of the weight force acting parallel to the slope is sinmg = 1.2 104 N sin 15 = 3.1 103 N The net force acting on the car is 2.1 103 N down the slope.

maF

mFa

kg 101.2N 101.2

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= 1.8 m s 2 down the plane.