The puck in the figure below has a mass of 0.120 kg. The distance of the puck from the center of rotation is originally 32.0 cm, and the puck is sliding with a speed of 80.0 cm/s. The string is pulled downward 12.5 cm through the hole in the frictionless table. Determine the work done on the puck. (Suggestion: Consider the change of kinetic energy.) 0 R m × Your response is off by a multiple of ten. J

A 51.6 kg sled coasts down a hill, starting from rest. The hill is inclined at an angle of 17.4 degrees with respect to the horizontal and has a height of 17.5 m. The coefficient of kinetic friction between the sled's blades and the hill is ??μs  = 0.11. What is the work done on the sled (in Joules) by the normal force?

A constant 82.5-N force acts on a 6.54-kg box. The box initially is moving at 20.5 m/s in the direction of the force, and some time later the box is moving at 57.7 m/s. Determine the work (in J) done by this force. You may assume that only one force acts on the box.

Starting from rest, a 4.2-kg block slides 2.20 m down a rough 30.0° incline. The coefficient of kinetic friction between the block and the incline is µk = 0.436. (a) Determine the work done by the force of gravity. (b) Determine the work done by the friction force between block and incline. (c) Determine the work done by the normal force.

A 27.0-kg child on a 4.00-m-long swing is released from rest when the ropes of the swing make an angle of 35.0° with the vertical. (a) Neglecting friction, find the child's speed at the lowest position. m/s (b) If the actual speed of the child at the lowest position is 3.30 m/s, what is the mechanical energy lost due to friction? Need Help? Read It

A sled has a total mass of 57 kg and is pushed with a horizontal force from rest. It accelerates at 3.1 m/s? and moves a distance of 93 m on a horizontal surface. The coefficient of kinetic friction between the sled and surface is 0.28. Find the work done by the pushing force. Round your final answer to a whole number.

Starting from rest, a 5.50-kg block slides 2.40 m down a rough 30.0° incline. The coefficient of kinetic friction between the block and the incline is  ?k = 0.436.   (a) Determine the work done by the force of gravity.(b) Determine the work done by the friction force between block and incline.(c) Determine the work done by the normal force.(d) Qualitatively, how would the answers change if a shorter ramp at a steeper angle were used to span the same vertical height?

A hockey puck of mass 0.26 kg is sliding along a slippery frozen lake, with an initial speed of 64 m/s. The coefficient of friction between the ice and the puck is eventually causes the puck to slide to a stop. Find the work done by friction. J = 0.031. Friction

A child on a sled is initially at rest on an icy horizontal surface. The sled is pushed until it reaches a final velocity of 6.05 m/s in a distance of 15.6 m. The coefficient of friction between the ice and runners of the sled is 0.200, and the weight of the child and the sled is 375 N. Find the work done by the force pushing the sled.

Starting from rest, a 4.70-kg block slides 3.40 m down a rough 30.0° incline. The coefficient of kinetic friction between the block and the incline is = 0.436. (a) Determine the work done by the force of gravity. (b) Determine the work done by the friction force between block and incline. (c) Determine the work done by the normal force. (d) Qualitatively, how would the answers change if a shorter ramp at a steeper angle were used to span the same vertical height?