Two blocks are connected by a string as in:   What is the upper block's acceleration if the coefficient of kinetic friction between the block and the table is 0.15? Express your answer with the appropriate units.

A student is trying to determine the critical angle (0) at which block will slide down an incline. She knows the coefficient of static friction between the incline and the block is 0.53 and the coefficient of kinetic friction is 0.44. Neglect drag. Hint: One way to solve the problem is to solve for all quantities in terms of m, e and g (but not u), then use f= uN and a trig identity to solve for 0. What is the critical angle? 13 Would the the block slide if the incline angle were 35°? cannot be det check answers I Rain to st

A 1,380-N crate is being pushed across a level floor at a constant speed by a force F of 320 N at an angle of 20.0° below the horizontal, as shown in the figure a below. a) What is the coefficient of kinetic friction between the crate and the floor? (Enter your answer to at least three decimal places.)(b) If the 320-N force is instead pulling the block at an angle of 20.0° above the horizontal, as shown in the figure b, what will be the acceleration of the crate? Assume that the coefficient of friction is the same as that found in part (a).m/s2

A 40 N box is resting on a table when a 20 N force is applied to it horizontally. The coefficients of static and kinetic friction are 0.3 and 0.1, respectively. Which of the following best describes the resulting motion of the box?    The motion of the box cannot be determined with the given information.      The box accelerates in the direction of the applied force.      The box remains at rest.      The box moves with a constant velocity in the direction of the applied force.

In the very Dutch sport of Fierljeppen, athletes run up to a long pole and then use it to vault across a canal as shown in (Figure 1). At the very top of his arc, a 70 kg vaulter is moving at 2.9 m/s and is 5.5 m from the bottom end of the pole. What is the magnitude of the vertical force that the pole exerts on the vaulter? Express your answer with the appropriate units.

At a construction site, a pallet of bricks is to be suspended by attaching a rope to it and connecting the other end to a couple of heavy crates on the roof of a building, as shown in (Figure 1). The rope pulls horizontally on the lower crate, and the coefficient of static friction between the lower crate and the roof is 0.509. What is the weight of the heaviest pallet of bricks that can be supported this way? (Hint: Start by drawing appropriate free-body diagrams.) (Express your answer in pounds.) What is the friction force on the upper crate under the conditions given in Part 1? (Express your answer in pounds.)

In the figure below, m, = 10.2 kg and m, = 4.3 kg. The coefficient of static friction between m, and the horizontal surface is 0.50, and the coefficient of kinetic friction is 0.30. An illustration shows a rectangular block of mass m, on the horizontal surface of a table. This is connected to another rectangular block of mass m, by a cord that runs over a pulley placed diagonally at the corner of the horizontal surface of the table. The rectangular block of mass m, is suspended vertically by the side of the tabletop. (a) If the system is released from rest, what will its acceleration be? (Enter the magnitude of the acceleration.) m/s? (b) If the system is set in motion with m, moving downward, what will be the acceleration of the system? (Enter the magnitude of the acceleration.) m/s2