A block slides to the right on a rough horizontal surface. The forces exerted on the block are shown above. Which of the following statements about the frictional force Ff exerted on the block is true?
A) It is the only force acting on the block that is caused by microscopic interactions.
B) It does not depend on the materials that the block and the surface are made of.
C) It is caused by gravitational interactions between the atoms in the block and the atoms in the surface.
D) It is the sum of all the microscopic contact forces between the bottom of the block and the surface.
Answers: 1
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A block slides to the right on a rough horizontal surface. The forces exerted on the block are shown...
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