Finding EMF Required for a 22A, 5 Ohm Heater Coil

AI Thread Summary
To determine the EMF required for a heater coil with a current of 22 amperes and a resistance of 5 ohms, Ohm's Law (V = IR) is applied. The initial calculation mistakenly referred to "velocity" instead of voltage, leading to confusion. The correct calculation shows that EMF equals the product of current and resistance, resulting in 110 volts. However, the total EMF must also account for any internal resistance, which was miscalculated in the discussion. The final consensus confirms that the EMF needed is 110 volts, aligning with Ohm's Law.
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Homework Statement


A current of 22 amperes flows in a heater coil whose resistance is 5 ohms. What E M F in volts is required?


Homework Equations





The Attempt at a Solution


Not quite sure where to begin. I'm thinking the internal resistance, R, is inherent w/the circuit so EMF must be greater than the velocity calculated.

Velocity =IXR=22x5=110
EMF=V +IR = 110 + 22x5=220 volts
Any comments here on if this is correct?
 
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Just V=IR
Review your variables before you plug and chug. V here is not velocity, it is the EMF.
 
porcupine6789 said:
Just V=IR
Review your variables before you plug and chug. V here is not velocity, it is the EMF.

So this would be ohm's law?
V=IR -->
EMF=(22)(5)=110 Ohms
 
Yeah, should be. Except the units of EMF is in volts. Resitance is ohms.
 

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