1.   State an equation that links power, energy and time.

2.   Calculate the missing values in the table below.

3.   Calculate the power of an appliance which consumes 200 J of energy in 100 s.

4.   A sewing machine has a power rating of 100 W. Calculate the time it will operate for on 3000 J of energy.

5.   A steam iron consumes 32 000 J of energy in 40 s. Calculate the power of the iron.

6.   A washing machine has an average power of 600 W over its was cycle.

(a)   How many joules of energy are used during a wash cycle lasting 30 minutes.

(b)   At times, the power rating of the washing machine is much higher than the average of 600 W. Suggest a reason for this.