You pull a short refrigerator with a constant force across a greased (frictionless) floor, either with horizontal (case 1) or with tilted upward at an angle u (case 2). (a)What is the ratio of the refrigerator’s speed in case 2 to its speed in case 1 if you pull for a certain time t? (b) What is this ratio if you pull for a certain distance d?

I was given this problem, and I don't really know what to do about the fact that the normal force doesn't equal the weight for this problem. How am I supposed to find the kinetic friction coefficient now? A box of mass 2,463g is on level ground being pulled by a force of 6.41N at angle 47.2 above horizontal. If the block is moving with a constant velocity, what is the kinetic friction coefficient? (Hint: the normal force does not always equal the weight; it does not in this case.)

A block of mass m = 2.90 kg is pushed a distance d = 7.80 m along a frictionless horizontal table by a constant applied force of magnitude F = 16.0 N directed at an angle ? = 24.0° below the horizontal as shown in the figure below. A block labeled m is on a horizontal surface. An arrow labeled vector F points downward and to the right at an angle ? above the horizontal, and acts upon the upper left corner of the block. A faded image of the block is a distance d to the right of the block. (a) Determine the work done on the block by the applied force. J(b) Determine the work done on the block by the normal force exerted by the table. J(c) Determine the work done on the block by the force of gravity. J(d) Determine the work done by the net force on the block.

You have devised an experiment to measure the kinetic coefficient of friction between a ramp and a mass. You place the mass on the ramp at an angle high enough that the mass starts sliding. You measure the time it takes to fall down a known distance. The time it takes to fall down the 45 degree ramp starting from a standstill is At = 0.46 sec, m=1 kg, and the distance it falls, Ax , is 0.5 m. What is µk? m Дх in At Uk