Power calculation of power resistor using different formulas

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Power calculation of power resistor using different formulas [Copy link]

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IIR and UI calculated by different power resistor formulas are different. For a 2515 resistor, 50 milliohms, a voltage of 12.6V at one end, and a current of 2.4A, the power consumption on the resistor is 2.4*2.4*0.05=0.288W by IIR, while 12.6*2.4=30.24W by UI, which is dozens of times different. Where is the calculation wrong? In theory, both formulas are OK, right? Shouldn't the voltage be 12.6V?

maychang

[50 milliohms, voltage at one end 12.6V, current flowing 2.4A]

Is there such a resistor?

Go back and retake your junior high school physics course.

乱世煮酒论天下

Why is it the voltage at one end, not the voltage at both ends?

艾默生321

If possible, please post a schematic diagram. It's a bit difficult to judge. I don't know what your circuit looks like.

well_kim

It should be the voltage difference across the resistor multiplied by the current

bigbat

Haha, the sofa is correct:

[50 milliohms, voltage at one end 12.6V, current flowing 2.4A]

Is there such a resistor?

Go back and retake your junior high school physics course.

Voltage is the voltage drop across a resistor!

qwqwqw2088

Is this correct? 2515 chip resistor, is there such specification?

qwqwqw2088

Brand: UNI-ROYAL (Housheng)
Manufacturer Model: 25121WJ050LT4E

Package: 2512

beyond_笑谈

2515 resistor, 50 milliohms, voltage at one end 12.6V, current flowing 2.4A,

This description should be wrong. I guess it is 2512, 50 milliohm resistor, and current 2.4A. The voltage drop across the resistor is determined by the current.

Calculation 1:

U=0.05*2.4=0.12V, P=0.12*2.4=0.288W

Calculation 2:

P=2.4*2.4*0.05=0.288W