Question

A bicyclist traveling at 24 km/h squeezes the brakes and slows down to a stop in 2.5 seconds. Which of the following statements best describes what happened to the energy of the moving bicycle? A The kinetic energy was converted to thermal energy. B The chemical energy was converted to mechanical energy. C The kinetic energy was converted to chemical energy. D The chemical energy was converted to thermal energy.

Answer 1

The correct answer is A: The kinetic energy was converted to thermal energy.

When a bicyclist squeezes the brakes and slows down to a stop, the kinetic energy of the moving bicycle is converted to thermal energy. This is because the brakes on a bicycle work by converting the kinetic energy of the moving bike into heat energy through friction. When the brakes are applied, the brake pads clamp down on the brake rotor, which is attached to the wheel. The friction between the brake pads and the brake rotor slows the wheel down and converts the kinetic energy of the moving bicycle into heat energy. This heat energy can then be dissipated through the brake pads and the brake rotor, causing the bicycle to come to a stop.

Step-by-step explanation:

Answer 2

A The kinetic energy was converted to thermal energy

Step-by-step explanation:

Friction braking is the most commonly used braking method in modern vehicles. It involves the conversion of kinetic energy to thermal energy by applying friction to the moving parts of a system. The friction force resists motion and in turn generates heat, eventually bringing the velocity to zero.