A skier of mass 61 kg is pulled up a slope by a motor-driven cable. (a) How much work is required to pull him 80 m up a 30° slope (assumed frictionless) at a constant speed of 2.9 m/s? kJ (b) What power (expressed in hp) must a motor have to perform this task? hp

A 1300-kg elevator carries a maximum load of 750 kg. A constant frictional force of 3000 N retards its motion upward. What minimum power, (in horsepower), must the motor deliver to lift the fully loaded elevator at a constant speed of 3.50 m/s?      1 horsepower = 746 W

a block of mass m=5 kg is pulled at a constant speed along a rough horizontal surface by a rope at 30 degree. the tension in the rope is T and the coefficient of kinetic friction between the block and the surface is 0.25. (a) find the tension in the rope. (b) if the block travels a distance of 4.5 m along the surface, what is the work done by the tension force from the rope? (c) find the work done by friction on the rock.

A shopper pushes a grocery cart 36.6 m on level ground, against a 13.1 N frictional force. The cart has a mass of 15.2 kg. He pushes in a direction 17.8º below the horizontal. If the initial velocity was 1.8 m/s, and final speed was 15.4 m/2. What is the work done by the pushing force in unit of Joule?

A heavy box is pulled by a rope on a horizontal surface. (a) Assume that there is no frictional force between the box and the surface. If the tension force in the rope is 240 N and the box moves by the distance of 5.6 m in 2.9 s, what is the power output of the work done by the tension force?  (b) Assume that the surface is rough and there is frictional force between the box and the surface. If the box moves at the constant speed of 0.31 m/s when the tension force is 240 N, what is the power output of the work done by the tension force?

An applied force of 20 N i pushes an object that is initially at rest over a horizontal surface. The coefficient of kinetic friction is 0.450 and the mass is 1.4 kg. If the net work done at some point is 60.6 J, what is the object's speed at that point?

A sledge loaded with bricks has a total mass of 18.7 kg and is pulled at constant speed by a rope inclined at 20.3° above the horizontal. The sledge moves a distance of 19.9 m on a horizontal surface. The coefficient of kinetic friction between the sledge and surface is 0.500. (a) What is the tension in the rope? (b) How much work is done by the rope on the sledge? kJ (c) What is the mechanical energy lost due to friction? k]

A sledge loaded with bricks has a total mass of 18.6 kg and is pulled at constant speed by a rope inclined at 20.8° above the horizontal. The sledge moves a distance of 20.9 m on a horizontal surface. The coefficient of kinetic friction between the sledge and surface is 0.500. (a) What is the tension in the rope? (b) How much work is done by the rope on the sledge? kJ (c) What is the mechanical energy lost due to friction? kJ

A car with the mass m=1600kg coasts down an incline from an initial height of h=7m with an initial speed v0=15m/s. When it reaches the bottom of the incline its speed is 20m/s. How much work did friction do on the car? This is the full question. No acceleration given. Assistance please.

A mechanic pushes a 3850 kg car from rest to a speed of v, doing 5083 J of work in the process. Find the speed v. Neglect friction between car and road. Answer in units of m/s.