Question

The potential difference across the lamp in the diagram is 12V. How many joules of electricity energy are changed into light and heat when a charge of 1c,5c and a current of 2A flows through it for 10 seconds?

Answer 1

Here we simply need to use, Work done = Potential difference × Charge to find the electrical energy utilised in the first two cases when we have the charge flowing. In the third case we can simply use, W = VIt

a. W = 12×1 = 12 J

b. W = 12×5 = 60 J

c. W = 12×2×10 = 240 J