4.04 Efficiency and Power

12345678910111213
Across
  1. 3. Humans spend energy stored in ________
  2. 5. Power is defined as the _______ of work done or energy transformed
  3. 7. Efficiency = __________ work done or energy / total energy input
  4. 8. Electric motors spend the energy supplied by battery or ____________
  5. 11. The __________ of an engine or system tells us the percentage or ratio of useful work done to the total energy input
  6. 12. An engine which is more powerful tend to do work at a __________ rate
  7. 13. The unit of power is ________ (W)
Down
  1. 1. Power = work done or energy transformed / _________
  2. 2. 1 ___________ = 746 W
  3. 3. Petrol engine spend the energy stored in _____
  4. 4. The efficiency of fuel-burning engines is low not because of poor ________ but because most of the energy transformation from fuel burning is wasted as heat
  5. 6. An engine does useful work with some of the energy provided but most of it is wasted as ________ energy
  6. 9. If an engine does 80 J of useful work when supplied with 100 J of energy, its efficiency is _______ percent
  7. 10. 1 W is also equal to 1 joule per ________