Which of the following must be happening if an object is in uniform circular
motion?
A. The object must be moving in a straight line.
B. The object's centripetal acceleration must be changing.
C. The object's velocity must be changing.
D. The object's speed must be changing.

Which describes increasing the efficiency of energy resource

You are your friend move a new refrigerator into his kitchen. you apply a horizontal force of 252 n in the negative x direction to try and move the 56 kg refrigerator. the coefficient of static friction is 0.61. (a) how much static frictional force does the floor exert on the refrigerator? give both magnitude (in n) and direction. magnitude n direction (b) what maximum force (in n) do you need to apply before the refrigerator starts to move?

Astudent pushes a 40-n block across the floor for a distance of 10 m. how much work was applied to move the block? a. 4 j b. 40 j c. 400 j d. 4000 j