Table lamp power 60 W. What is its resistance if the voltage in the network is 120 V?

Given:

W = 60 watts – the power of the table lamp;

U = 120 Volts – electrical circuit voltage.

It is required to determine R (Ohm) – the resistance of a table lamp.

Find the strength of the current flowing in the table lamp:

I = W / U = 60/120 = 1/2 = 0.5 Ampere.

Then the resistance of the lamp will be equal (according to Ohm’s law):

U = I * R, from here we find:

R = U / I = 120 / 0.5 = 240 ohms.

Answer: The resistance of the table lamp is 240 ohms.