. When a driver applies brakes to keep a car going downhill at constant speed and constant kinetic energy, the potential energy of the car decreases. Where does this energy go? Where does most of it appear in a hybrid vehicle?

Answer 1

The energy is converted to heat in from the friction of the brakes slowing the car down. It is released through the brake disks or brake drums.
While braking a hybrid vehical this energy is used to charge the reserve batteries for later use.

Answer 2

To the wheels

Answer 3

No, the energy is not transferred to the wheels. When the brakes are applied in a car, the brake pads create friction with the brake rotors or drums, which converts the kinetic energy of the moving car into heat energy. This heat energy is dissipated through the brake components and ultimately into the surrounding air. In a hybrid vehicle, a portion of this heat energy can be captured and converted into electrical energy using regenerative braking, which is then stored in the battery for future use.