1. An electric light bulb is 80% efficient. If it uses 300J of electrical energy how much light energy will it produce ? What happens to the rest of the energy ?
2. A small pulley is used to lift a load and give it 400J of potential energy. If the person using the pulley
supplied it with 3000J of energy, how efficient is the pulley ?
3. The efficiency of a car jack is 25%. It takes 1000J of energy to lift a car high enough to change the
wheel. How much energy must someone using the jack put in ?
10 points per. question!!!!!!!!!!!!!!!!!!!PLEASE