Converting Watts to Volts: Maximum Current for a 3.5W Resistor

AI Thread Summary
To determine the maximum current for a 3.5W, 220-ohm resistor, the relevant formulas are P=IV and P=I^2R. By substituting the values, the equation simplifies to 3.5W = I^2 * 220 ohms. Solving for I gives I^2 = 3.5/220, resulting in I = 0.1581 amps. The calculation method is confirmed as correct, despite a minor typo in the square root step. Understanding these formulas is essential for accurate electrical calculations.
haleyscavone
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What is the maximum current allowed in a 3.5 W, 220 ohm resistor?

The answer needs to be in amps so how would I convert watts to volts?
 
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Whats the formula for power dissapation in a resistor?
hint, V=IR and P=IV
 
Because the voltage was unknown you would use both equations and substitution right?
So P=I(IR) ---> P=I^2R

So 3.5/220=I^2
.0159=I^2
I=.1581

Is that correct?
 
Slight typo/mistake in your sqrt but yes - that's the correct method
 
thank you!
 
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