A baseball player with mass m = 79 kg, sliding into second base, is retarded by a frictional force of magnitude 470 N.What is the coefficient of kinetic friction mk between the player and the ground?

A constant force Fa pushes a 22.5-kg box across a rough horizontal surface. The magnitude of Fa is 185 N and the force is inclined at an angle of θ = 30.0° below the horizontal. The coefficient of kinetic friction between the box and the surface is μk = 0.500. What is the magnitude of the box's acceleration?

A 7.5 kg backpack is sliding across the floor.  The coefficient of friction between the backpack and the floor is 0.20.  Answer the following:   Is this static or kinetic friction?

Problem 1: While training on the planet Dagobah, Luke Skywalker is asked by Yoda to hold a block with a mass of 6.80kg against a vertical wall using only the Force. Luke applies the Force with a magnitude of 115.0N at an angle of 52.0° with respect to the horizontal. Luke discovers that if the Force increases any more, the block begins to slide up the wall. What is the coefficient of static friction between the block and the wall? Assume that gravity on Dagobah is the same as gravity on Earth.

A woman exerts a horizontal force of 111 N on a box with a mass of 31.7 kg. HINT (a) If the box doesn't move, what's the magnitude of the static friction force (in N)?  N (b) What is the minimum possible value of the coefficient of static friction between the box and the floor? (Assume the box remains stationary.)

Question 8. A 5.41-kg box is sliding across the horizontal floor of an elevator. The coefficient of kinetic friction between the box and the floor is 0.369. Determine the kinetic frictional force that acts on the box when the elevator is (a) stationary, (b) accelerating upward with an acceleration whose magnitude is 2.64 m/s², and (c) accelerating downward with an acceleration whose magnitude is 2.64 m/s².Ans: 19.56 N; 24.83 N; 14.29 N

A block is placed on the midpoint of a ramp that is inclined at an angle of 39.8º from the horizontal, at which point the block immediately starts to slide down the ramp due to the fact that the static friction limit for this particular case is insufficient to hold the block in place. If the coefficient of kinetic friction between the block and the ramp is  0.277 , what is the magnitude of the acceleration of the block as it slides down the ramp.

A large cube (mass = M) being accelerated across a horizontal frictionless surface by a horizontal force . A small cube (mass = m) is in contact with the front surface of the large cube and will slide downward unless is sufficiently large. The coefficient of static friction between the cubes is u. What is the smallest magnitude that F can have in order to keep the small cube from sliding downward?

A girl exerts a horizontal force of 133 N on a box with a mass of 33.2 kg.   (a) If the box doesn't move, what's the magnitude of the static friction force (in N)? N (b) What is the minimum possible value of the coefficient of static friction between the box and the floor? (Assume the box remains stationary.)

Scenario: You pull on a 7.9 kg block with a rope exerting a 34 N tension force that is directed 16 degrees above horizontal. If you were to pull the tiniest bit harder, the block would move, but at this tension the block stays put. Question: What is the coefficient of static friction between the block and floor?