Wasted energy

Not all energy is changed into the type we want

Identify the useful and wasted energy

Identify the useful and wasted energy

Identify the useful and wasted energy

What is the difference between the energy transformation in these two bulbs?

Which might be the most efficient (waste the leave energy) ?

Measure the electrical energy going into each of these bulbs.Use this information to calculate the efficiency of each bulb

Filament bulb Low energy bulb

Electrical energy entering each bulb

Light energy emitted 6W 5W

Heat energy emitted 50W 6W

Plenary

Phone charger Light bulb

Electrical energy in (W) 1W 60W

Energy out (W) Heat 0.2 WElectrical 0.8W

Light 6WHeat 54W

Which of these is most efficient?