Edexcel GCSE Physics Topic 3 Conservation of energy overview quiz quiz

$\Delta GPE = m \times g \times \Delta h$

$\Delta GPE = \frac{1}{2} m v^2$

$\Delta GPE = F \times d$

$\Delta GPE = m \times c \times \Delta\theta$

$5\,\text{J}$

$25\,\text{J}$

$10\,\text{J}$

$50\,\text{J}$

Kinetic store to gravitational store

Thermal store to kinetic store

Gravitational store to kinetic store

Elastic store to gravitational store

Heating something up

Electrically by a current

Radiation as light

The elastic store

Energy cannot be created or destroyed, only transferred or dissipated

Energy is always completely lost as heat whenever it is being transferred

The total energy always increases steadily inside any closed system

Energy can only ever be stored as kinetic energy and nothing else

The kinetic store of the moving object

The thermal store of the surroundings

The chemical store inside the fuel or food

The gravitational store of the raised object

It adds extra energy directly into the machine as it runs

It increases the total mass of all the moving parts of the machine

It reduces friction, so less energy is dissipated as heat

It increases the thermal conductivity of the moving metal parts

They increase the rate of cooling

They have no effect

They stop cooling completely

They reduce the rate of cooling

$\frac{\text{useful energy transferred}}{\text{total energy supplied}}$

$\frac{\text{total energy supplied}}{\text{useful energy transferred}}$

$\frac{\text{wasted energy}}{\text{total energy supplied}}$

useful energy $\times$ total energy

$10\%$

$25\%$

$50\%$

$75\%$

Some of the energy is actually destroyed inside the device as it runs

The efficiency of a device cannot ever be measured accurately

Some energy is always dissipated, usually as heating

Devices always gain extra energy from their surroundings

The temperature of the device

The power of the device only

The efficiency of the device only

The amount of energy