The operating potential difference of a light bulb is 120 V. The power rating of the bulb is 75 W. Find the current in the bulb and the bulb's resistance.

Answer 1

We can use the formula for electrical power:

P = V*I

where P is the power in watts, V is the voltage in volts, and I is the current in amperes.

We know that the power rating of the bulb is 75 W and the operating potential difference is 120 V, so we can rearrange the formula to solve for the current:

I = P/V = 75 W / 120 V = 0.625 A

Now that we know the current, we can use Ohm's law to calculate the resistance of the bulb:

R = V/I = 120 V / 0.625 A = 192 Ω

Therefore, the current in the bulb is 0.625 A and the resistance of the bulb is 192 Ω.