###### Asked in Consumer ElectronicsHome AppliancesIndustrial EngineeringThomas Edison

Consumer Electronics

Home Appliances

Industrial Engineering

Thomas Edison

# Why does an electric iron have a resistance of 15 ohms?

## Answer

###### Wiki User

###### November 02, 2007 7:38PM

I never measured the resistance of an electric iron, but: the 15 ohm resistance is probably required to develop a required 806 watts of power. Using Ohm's law, I(current) = E(voltage)/R(resistance), therefore

I(current) =110 volts/15 ohms = 7.33 Amps (current), and, Power (watts) = E(voltage) X I(current); 110 volts X 7.33 amps = 806 watts. The iron requires that wattage to develop enough heat in the sole of the iron. Hope this helps.

## Related Questions

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### A portable electric heater has a resistance of 15 ohms It plugs into a wall outlet that is 120 V How much current does it draw?

The formula we need to use is called "Ohm's Law":
E = I x R
which can also be stated as:
R = E / I
or as:
I = E / R
where I = current (amps), E = potential difference (volts) and R
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"x" means "multiply by" and "/" means "divide by".
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If current of 15 amps runs through a hair dryer while the
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Note: 150 volts is inconsistent with normal US household voltage
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or so) average current permitted for a 15 amp circuit. This
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