Q11 of 330 Page 58

What current will be taken by a 920 W appliance if the supply voltage is 230 V.

Here P = 920W, V = 230V, I = ?

We know that

P = V x I

920 = 230 x I

I = 920/230 = 4amp

If the potential difference between the end of a wire of fixed resistance is doubled, by how much does the electric power increase?

An electric lamp is labeled 12 V, 36 W. This indicates that it should be used with a 12 V supply. What other information does the label provide?

Define watt. Write down an equation linking watts, volts and amperes.

Define watt-hour. How many joules are equal to 1 watt-hour?