Question

A softball player hits a ball at 78 miles per hour. Then she hits a ball at 80 miles per hour. Which is the best prediction?(1 point)
Responses

The ball hit at 78 miles per hour will have more kinetic energy.
The ball hit at 78 miles per hour will have more kinetic energy.

The balls will have the same amount of kinetic energy.
The balls will have the same amount of kinetic energy.

The ball hit at 80 miles per hour will have more kinetic energy.
The ball hit at 80 miles per hour will have more kinetic energy.

The balls’ kinetic energies will depend on the distances they travel.

Answer 1

The ball hit at 80 miles per hour will have more kinetic energy.

Reason: Kinetic energy = 1/2 · m · v^2. If the balls have the same mass, KE is proportional to v^2, so (80/78)^2 ≈ 1.052 — about 5.2% more energy for the 80 mph shot.