A force of 120 newtons (N) was applied to a pulley to lift an object a height of 1 meter (m). If 100 joules (J) of work was done on the weight, how much work was used to overcome the force of friction in the pulley?

A. 1.2 joules

B. 20 joules

C. 120 joules

D. 220 joules

Abearing is designed to a reduce friction b. support a load c.guide moving parts such as wheels, shafts and pivots d. all of the above

An engineer designs a roller coaster so that a car travels horizontally for 152 ft, then climbs 137 ft at an angle of 34.0° above the horizontal. it then moves 137 ft at an angle of 48.0° below the horizontal. if we take the initial horizontal motion of the car to be along the +x-axis, what is the car's displacement? (give the magnitude of your answer, in ft, to at least four significant figures and give the direction of your answer in degrees counterclockwise from the +x-axis.)

Which explanation describes the forces involved for a person to walk down the sidewalk? a. the person's feet push backward on the sidewalk; the sidewalk pushes backward on the person. b. the person's feet push forward on the sidewalk; the sidewalk does not push on the person. c. the person's feet push backward on the sidewalk; the sidewalk pushes forward on the person. d. the person's feet push forward on the sidewalk; the sidewalk pushes forward on the person.