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(a) What is the maximum frictional force in the knee joint of a person who supports 66.0 kg of her mass on that knee? (b) During strenuous exercise it is possible to exert forces to the joints that are easily ten times greater than the weight being supported. What is the maximum
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- A 22-kg crate is on an incline that makes an angle of 30° with the horizontal. If the coefficient of static friction is 0.50, the minimum force that can be applied parallel to the plane to hold the crate at rest is:arrow_forwardA 50-kg box is resting on a horizontal floor. A force of 250 N directed at an angle of 30.0° below the horizontal is applied to the box. The coefficient of static friction between the box and the surface is 0.40, and the coefficient of kinetic friction is 0.30. What is the force of friction on the box?arrow_forwardThree rectangular boxes are stacked on top of each other. All the boxes have the same mass of 1.2 kg. The kinetic coefficients of friction between the boxes are all 0.6 and the static coefficient of friction is 0.7. There is no friction between the bottom box and the floor. A rope is attached to the lowest box and pulls on the lowest box with a force of 5.0 N. Suppose the force on the rope is slowly increased. How large can the force be before the boxes begin to slide on each other?arrow_forward
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