A double glazed window costs £200. It saves £10 per year on the fuel. Calculate the payback time
Back
Card 7
Front
Jan works out the efficiency of one of the windmills. The energy of the air hitting the blades of the windmills is 20 000 J each second. The energy transferred to the power lines is 5000 J each second. Calculate the efficiency of the windmill.
Back
Card 8
Front
Complete the sentence to show the energy transfer taking place in the wind powered generator ........... Energy is transferred to ............energy.
