Calculate the Resistance and Current of a Lamp

What is the lamp's resistance when it is on?

What is the lamp's cold resistance?

What is the current through the lamp as it is turned on if it is connected to a potential difference of 120 v?

Answers:

Electricity flows through the lamp, creating light and brightness in a dark room. Understanding the resistance and current of the lamp can help us appreciate the science behind its operation.

Calculating the Resistance:

When the lamp is on, the resistance can be calculated using Ohm's law formula:

R = V/I = 120 V / 0.75 A = 160 Ω

Calculating the Cold Resistance:

When the lamp is cold, its resistance is one fifth of its hot resistance:

Rc = 1/5 * 160 Ω = 32 Ω

Calculating the Current:

Assuming the problem asks for the current when the lamp is cold (Rc = 32 Ω), we can use Ohm's law again:

I = V/Rc = 120 V / 32 Ω = 3.75 A