Question

an electric lamp consumes 100w of power. if supply voltage is 220v. how much energy consumed in 30 minutes

Answer 1

Question

As we know the power is the energy divided by the time, so, we can see that energy is the power multiplied by the time. So, we will have:

$$E = P \cdot t = 100 \left(\frac{J}{\sec}\right) \cdot 1800(\sec) = 180000(J).$$

Answer: the energy is 180000 Joules.