Question

which example best demonstrates how unbalanced forces change the speed of an objects motion? a a child on a bicycle braking at a stop sign. b a child singing a song. c a child sitting in a chair reading a book. d a child walking around the corner of a school hallway.

Explanation:

Unbalanced forces change an object's speed or direction. When a child on a bicycle brakes at a stop - sign, the braking force is an unbalanced force that reduces the bicycle's speed. In option A, walking is a normal motion without a clear change in speed due to unbalanced forces. In option B, singing is a non - motion related activity. In option C, sitting and reading is a static activity with no change in motion due to unbalanced forces.

Answer:

A. A child on a bicycle braking at a stop sign.