Concept explainers
A block is resting on a rough inclined surface. You observe that by increasing the angle of the incline, you can make the block start moving down the incline. Which answer best explains why the block starts moving?
a. By increasing the angle of the incline, you increase the component of the force exerted by Earth on the block, which pulls the block down the incline.
b. By increasing the angle of the incline, you decrease the maximum static friction force exerted on the block by the surface
c. by increasing the angle of the incline, you simultaneously increase the component of the force exerted by Earth on the block and decrease the maximum static friction force exerted on the block.
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College Physics
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