A battery-powered toy car drives up a slope.
The Table shows the changes in energy stores during the journey.
Table
| Energy store | Change in energy in J\text{J}J |
|---|---|
| chemical store of the battery | decrease of 60 |
| gravitational potential energy store of the car | increase of 12 |
| kinetic store of the car | increase of 6 |
| thermal store of the motor, wires and surroundings | increase of XXX |
Gravitational field strength (ggg) = 10 N/kg
Calculate the value of XXX.
The mass of the car is 0.40 kg.
Calculate the vertical height gained by the car.
State the way in which energy is transferred from the battery to the motor.
The car, the slope and the surroundings can be treated as a closed system.
Explain why the total energy of this system does not change.