3 Conservation of energy

F

A student compares four devices. The table shows the energy transfers during one operation of each device.

Device	Total energy input in $J\mathrm{J}$	Wasted energy output in $J\mathrm{J}$
P	500	150
Q	800	200
R	600	180
S	1000	300

Which device has the greatest efficiency?

[1]

device Q

device P

device R

device S

F

A student compares four devices. The table shows the energy transfers during one operation of each device.

Device	Total energy input in $J\mathrm{J}$	Wasted energy output in $J\mathrm{J}$
P	500	150
Q	800	200
R	600	180
S	1000	300

Which device has the greatest efficiency?

[1]

device Q

device P

device R

device S

3 Conservation of energy Questions