# How would you use an ohmmeter to check the status of a light bulb?

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## Can you Ohm a light bulb?

Check the bulb by determining the resistance of the filament. The filament is the wire inside of the bulb. The resistance can be checked by a multimeter. By setting the multimeter selector switch to ohms it will read ohms for you.

## How do you check continuity on a light bulb?

Touch one lead to the small metal knob on the bottom of the bulb and the other lead to the bulb threads. If the bulb doesn’t have threads, put the second lead on one of the two knobs that protrude from the side of the base. The bulb is good if the meter reads zero of the tester bulb lights up.

## How do you calculate the resistance of a light bulb?

Since it involves the relationship of power voltage, current, and resistance, using the formula I=P/V with P and V known to find the current, and then using the formula R=P/I^2 to find the resistance will be the right steps to take.

## Can you use a multimeter as a test light?

If you don’t happen to have a working bulb handy, you can use a light socket tester or test the fixture with a multimeter. … There are two procedures to check a light socket with a multimeter, one of which requires the power to be on and another you can do with the power off.

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## What do we use to measure resistance?

Resistance is measured using an instrument such as an analog multimeter or digital multimeter. … As a result, a circuit’s resistance value can be determined if the current and voltage measured values are known. Analog multimeters and digital multimeters employ the measurement principle of Ohm’s Law to measure resistance.

## How many ohms is a light bulb?

The typical cold resistance of a 100 W incandescent lamp is about 9.5 ohms. If that resistance stayed the same with 120 V applied, Ohm’s Law tells us that the bulb would draw about 12.5 amps and dissipate about 1,500 watts.