A 3.5 kg block is pushed along a horizontal floor by a force of magnitude 15 N at an angle 40 with the horizontal . The coefficient of kinetic friction between the block and the floor is 0.25. Calculate the magnitudes of (a) the frictional force on the block from the floor and (b) the block’s acceleration.

A block is pressed against a vertical wall by a force F, as the drawing shows. This force can either push the block upward at a constant velocity or allow it to slide downward at a constant velocity. The magnitude of the force is different in the two cases, while the directional angle is the same. Kinetic friction exists between the block and the wall, and the coefficient of kinetic friction is 0.260. The weight of the block is 47.0 N, and the directional angle for the force F is 0 = 48.0°. Determine the magnitude of F when the block slides (a) up the wall and (b) down the wall. (a) P = (b) P= i i P >

A rope exerts a force of 50 N on a box to keep it stationary. If the box is on a plane inclined 25° from the horizontal and the coefficient of static friction is 0.29, calculate the normal force exerted on the box.

A roller-coaster car is towed up an incline at a steady speed of 0.500 m/s by a chain parallel to the surface of the incline. The slope is 3.00%, which means that the elevation increases by 3.00 m for every 100.0 m of horizontal distance. The mass of the roller-coaster car is 594 kg. Ignoring friction, what is the magnitude of the force exerted on the car by the chain?

A 2.5 kg block is initially at rest on a horizontal surface. A horizontal force F of magnitude 6.2 N and a vertical force P are then applied to the block. The coefficients of friction for the block and surface are us = 0.38 and uk = 0.22. (a) Determine the magnitude of the frictional force acting on the block if the magnitude of P is 8.0 N. (b) Determine the magnitude of the frictional force acting on the block if the magnitude of P is 10.0 N. (c) Determine the magnitude of the frictional force acting on the block if the magnitude of P is 12.0 N.

A block of mass 1.45 kg is resting on a board with friction.The board is inclined until the mass just starts to slide.  If the angle of the incline when the mass just barely begins to slide is 17.5 degrees,what is the coefficient of static friction between the block and the board?

The force acting on a particle has a magnitude of 166 N and is directed 29.4° above the positive x-axis. (a) Determine the x-component of the force.  (b) Determine the y-component of the force.

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.