Question

A 3.0-kg sphere was moving at 25 m/s when it hit another object. This caused all KE to be converted into thermal energy. What was the increase in thermal energy?

38 J
75 J
940 J
1900 J

Answer 1

The increase in thermal energy is 937.5 J.

Step-by-step explanation:

The increase in thermal energy can be calculated by subtracting the initial kinetic energy from the final thermal energy. The initial kinetic energy can be determined using the equation KE = 0.5 * mass * velocity^2. In this case, the initial kinetic energy is 0.5 * 3.0 kg * (25 m/s)^2 = 937.5 J. Since all of the initial kinetic energy is converted into thermal energy, the increase in thermal energy is equal to the initial kinetic energy, which is 937.5 J.

Answer 2

940 J

Step-by-step explanation:

Thermal energy = kinetic energy

KE = ½ mv²

KE = ½ (3.0 kg) (25 m/s)²

KE = 937.5 J

Rounding to 2 significant figures, the increase in thermal energy is 940 J.