Question

the diagrams below show a person moving a 50 - kilogram object up a ramp. in which diagram is there the least amount of friction on the object?
a: a person moving a 50 kg object up a ramp with rough surface, the height of the ramp - forming block is 1 meter.
b: a person moving a 50 kg object up a ramp with smooth surface, the height of the ramp - forming block is 1 meter.
c: a person moving a 50 kg object up a ramp with rough surface and wheels, the height of the ramp - forming block is 1 meter.
d: a person moving a 50 kg object up a ramp with smooth surface and wheels, the height of the ramp - forming block is 1 meter.

Explanation:

Friction depends on surface roughness and contact type. Smooth surfaces reduce friction more than rough ones, and wheels convert sliding friction to rolling friction (lower friction). Diagram D combines both a smooth surface and wheels, resulting in the least friction.

Answer:

D. (Diagram D: 50 kg object on wheels, smooth surface)