unit of temperature coefficient of copper

Temperature can be a beast if used with other units than Kelvin.

You have distinguish between absolute temperature and temperature difference. Prime has different units for both of them.

A temperature difference of 1 °C equals 1 K, but an absolute temperature of 1 °C equals 274.15 K.

That said, I guess that what you need is

and this would be the very same as

See here some example which maybe can explain the confusion

Hi @SZ_11156868,

I wanted to see if you got the help you needed.

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Thanks,
Anurag