A moving company uses a machine to raise a 900-newton refrigerator to the second floor of a building. The machine consists of a single pulley with a mechanical advantage of 1. How many newtons of input force will it take to raise the refrigerator? A. 1 N B. 100 N C. 450 N D. 900 N E. 9,000 N

You are helping your friend move a new refrigerator into his kitchen. You apply a horizontal force of 273 N in the negative x direction to try and move the 53 kg refrigerator. The coefficient of static friction is 0.68.(a)How much static frictional force does the floor exert on the refrigerator? Give both magnitude (in N) and direction.magnitude Ndirection (b)What maximum force (in N) do you need to apply before the refrigerator starts to move? N

A system of pulleys is used to raise a load of bricks that weighs 1,700 newtons. The force applied to the pulley is 340 newtons. What’s the mechanical advantage of this machine? A. 1 B. 2 C. 5 D. 10

Find the force needed to lift a 2,000 N weight using a machine with a mechanical advantage of 15.

An input force of 80 N is used to lift an object weighing 240 N with a system of pulleys.  How far down must the rope around the pulleys be pulled in order to lift the object a distance of 1.4 m?

A worker pushing a 35.0 kg wooden crate at a constant speed for 12.0 m along a woodfloor does 350 J of work by applying a constant horizontal force of magnitudeF on the crate.(a) Determine the value of F.(b) If the worker now applies a force greater than F, describe the subsequent motion ofthe crate.(c) Describe what would happen to the crate if the applied force is less than F.