# IB Physics Static and Kinetic Friction

A tutorial sheet on static and kinetic friction problems from subtopic 2.2 forces is given below

1. A 3.0 kg block is at rest at rest on each of two rough inclined planes. One incline makes an angle of 37° with the horizontal, the other 53°. On which block is a greater force of static friction acting?
2. A block of mass 2.0 kg is on a rough horizontal table. The coefficient of static friction between the block and the table is 0.4. A horizontal force of 5.0 N to the right is applied to the block. What is the force of static friction between the block and the table?
3. A block of wood of mass 4.0 kg has a brick of mass 2.0 kg sitting on it. The block rests on a smooth horizontal surface and the block and brick are initially at rest. A constant horizontal force of 12.0 N is applied to the block. What are the speeds of the block and the brick after 12.0 s? Assume that the brick stays on the block and that the coefficients of static friction and kinetic friction between the surfaces are 0.2 and 0.1 respectively.
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