Hello I've been stuck with this for ever, cant find the relevant formulas(adsbygoogle = window.adsbygoogle || []).push({});

1. The problem statement, all variables and given/known data

Given that the surface area of the first heat sink, S1= 500 cm2 = 0.05 m2

2nd heat sink = ?

The thermal resistance between p-n junction and case, RTjb = 0.6˚C/W

The thermal resistance between the case and any heat sink, RTbh = 1.2˚C/W

Power loss, P = 25W

The ambient air temperature, Ta= 20˚C

Heat transfer coefficient, α = 8 W/m2˚C

2. Relevant equations

so how do I find out the area of the second heat sink?

3. The attempt at a solution

Don't know how to start..

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# How do I find out the are of a heat sink when two heat sinks are attached to a semico

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