A 15.0-kg box of books is initially at rest on a horizontal floor. The coefficient of friction between the box and the floor is 0.5. What is the friction force (in Newtons) if a horizontal force of 70 N is applied?

A box of banana weighing 40.0 N rests on a horizontal surface. The coefficient of static friction between the box and the surface is 0.40, and the coefficient of kinetic friction is 0.20. (a) If no horizontal force is applied to the box and the box is at rest, how large is the friction force exerted on the box? (b) What is the magnitude of the friction force if a monkey applies a horizontal force of 6.0 N to the box and the box is initially at rest? (c) What minimum horizontal force must the monkey apply to start the box in motion? (d) What minimum horizontal force must the monkey apply to keep the box moving at constant velocity once it has been started? (e) if the monkey applies a horizontal force of 18.0 N, what is the magnitude of the friction force and what is the box's acceleration?

A 12.1 kgkg box sits on a horizontal table. A string with tension 30.6 NN pulls on the box to the right, but static friction between the box and the table prevents the box from moving.  The coefficient of static friction between the box and the table is 0.43.  What is the magnitude of the static friction force on the box?

You managed to pull a heavy crate up a ramp on a truck. The crate has mass 50 kg. You were pulling with 480 N of force along the ramp while the ramp made an angle of theta=25.0 degrees with the horizontal. The coefficient of kinetic friction between the crate and the ramp is 0.49. What is the acceleration of the crate along the ramp?

A worker pulls a 15-kg crate in a straight line on a level surface by imparting a horizontal tension of 80 N to the free end of a cable whose other end is attached to the crate. If the coefficient of static friction is 0.40, what is the acceleration of the crate?

You managed to pull a heavy crate up a ramp on a truck. The crate has mass 48 kg. You were pulling with 464 N of force along the ramp while the ramp made an angle of theta=29.5 degrees with the horizontal. The coefficient of kinetic friction between the crate and the ramp is 0.45. What is the acceleration of the crate along the ramp? FA

A carpenter attempts to push a sanding block across the wooden board. The maximum static friction between the sanding block and the wooden board is 25N. What is the sanding block's acceleration in the x direction if the carpenter pushes the block with a force of 20N.

A man exerts a northward force of 100 newtons on a 50 kilogram box which sits on a level floor. If the frictional force is 80 newtons, what is the magnitude of the northward acceleration of the box?

A rope inclined with 25^o has a tension of 120 N that pulls a 25 kg box along a horizontal floor. If the coefficient of kinetic friction between the floor and the box is 0.22, what is the Normal force on the box?

A force F is used to hold a block of mass m = 4.00 kg on an incline as shown in the diagram. The plane makes an angle of 0 = 30.0° with the horizontal and F is perpendicular to the incline. The coefficient of static friction between the plane and the block is 0.300. What is the minimum force, F in Newtons, necessary to keep the block at rest?