So I have a circuit setup 15v dc and a 220 R. My goal is to calculate the correct power rating and replace the current 1/4 resistor if a new one is appropriate.

source:

15V/220R ohm = .068 amps

the resistor:

P = I^2R

P = (.068 amps )^2 x (220 ohms)

P = 1.017 watts

The P(watts) looks high to me. Is my P correct? If so is it supposed to be doubled for safety sakes? Also so far one has not been burned up.

source:

15V/220R ohm = .068 amps

the resistor:

P = I^2R

P = (.068 amps )^2 x (220 ohms)

P = 1.017 watts

The P(watts) looks high to me. Is my P correct? If so is it supposed to be doubled for safety sakes? Also so far one has not been burned up.

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