How to Calculate Power Rating of Lamps Connected in Series

What is the rated power of the lamps connected in series?

Two lamps rated 220V each are connected in series. If the total power dissipated in both lamps is 80W, what is the rated power of the lamps?

Answer:

The rated power of each lamp connected in series can be calculated by dividing the total voltage equally among both lamps and using the total power provided to compute the current. Then, you can determine the power rating for each identical lamp using the formula P = IV.

When two lamps are connected in series, the total voltage is divided equally between them. In this case, each lamp is rated at 220V. This means that the total voltage across both lamps is 440V (220V + 220V). If the total power dissipated in both lamps is 80W, we can calculate the current flowing through the circuit.

Using the formula for power, P = IV, we can rearrange it to solve for current: I = P/V. Plugging in the values, we have I = 80W / 440V = 0.1818A. Since the lamps are connected in series, the current flowing through each lamp is the same.

Now, we can calculate the power rating of each lamp. Since the voltage is divided equally in a series circuit, each lamp receives half of the total voltage. Therefore, the voltage across each lamp is 220V / 2 = 110V.

Finally, using the power formula P = IV, we can calculate the power rating of each lamp: P = 0.1818A * 110V ≈ 20W. So, the rated power of each lamp connected in series is approximately 20W.