Question

Which situation shows a non-contact force changing the speed of an object?

Raking a leaf
A person riding a bike and moving the pedals faster
A nail rolls off the edge of a roof and falls to the ground
A batter hitting a baseball

Answer 1

The situation that shows a non-contact force changing the speed of an object is "A nail rolls off the edge of a roof and falls to the ground."

In this scenario, the nail is acted upon by gravity, which is a non-contact force, as it does not require direct contact with another object to exert its influence. The gravitational force causes the nail to accelerate downward, changing its speed as it falls.

In contrast, the other situations involve contact forces: raking a leaf involves a physical interaction, a person pedaling involves mechanical force through contact, and a batter hitting a baseball also involves direct contact.