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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.

## What is the resistance of electric 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.

## How do you calculate electric resistance?

**R = V ÷** I Question

What is the resistance of the lamp? To calculate the resistance of an electrical component, an ammeter is used to measure the current and a voltmeter to measure the potential difference. The resistance can then be calculated using Ohm’s Law.

## What is the resistance of a 200 watt light bulb?

So, the resistance is **312.5 ohms**.

## How can we calculate the exact current and resistance of 100 W bulb?

Also, Power can be calculated by P=I*E current in amps times voltage, for example, one amp and one hundred volts =100 watts. Resistance can be calculated by **R= E/I , voltage divided by current in amps**.

## What is the resistance of a 12v bulb?

Each incandescent bulb (12-volt/system) measures **1.5 ohms** with a meter; however, there is no resistance across the LED [replacement] bulbs.

## How do you solve for resistance?

**Ohms Law and Power**

- To find the Voltage, ( V ) [ V = I x R ] V (volts) = I (amps) x R (Ω)
- To find the Current, ( I ) [ I = V ÷ R ] I (amps) = V (volts) ÷ R (Ω)
- To find the Resistance, ( R ) [ R = V ÷ I ] R (Ω) = V (volts) ÷ I (amps)
- To find the Power (P) [ P = V x I ] P (watts) = V (volts) x I (amps)

## What is the equation for resistivity?

Resistivity, commonly symbolized by the Greek letter rho, ρ, is quantitatively equal to the resistance R of a specimen such as a wire, multiplied by its cross-sectional area A, and divided by its length l; **ρ = RA/l**. The unit of resistance is the ohm.

## What is the resistance of a small light bulb?

(A typical bulb has a resistance of **7 to 8 ohms through the filament** and 2 to 3 ohms through the shunt once the coating burns off.) Although you can buy simple 50-bulb strands like the one shown above, it is more common to see 100- or 150-bulb strands.

## Why does a light bulb have resistance?

The filament of a light bulb is an extremely thin wire. This thin wire **resists the flow of electrons**.

## Does higher resistance mean brighter bulb?

An incandescent bulb’s brightness depends on a whole lot on resistance. **The higher the resistance to current in the wiring**, circuitry, and bulb, the lower will be the current, lower the power, and lower the brightness. Conversely, lower resistance means more brightness.

## Are bulbs brighter in series or parallel?

Two light bulbs on the same series circuit share the voltage of the battery: if the battery is 9V, then each bulb gets 4.5 volts. … Two bulbs in a simple parallel circuit each enjoy the full voltage of the battery. This is why the **bulbs in the parallel circuit will be brighter than those in the series circuit**.