I don't understand newtons law of cooling(adsbygoogle = window.adsbygoogle || []).push({});

dT/dt = k(a - b)

were a is the object and b is the surroundings that the object is placed in...

Is this correct or is there suppose to be a negative sign like so

dT/dt = -k(a - b)

also does newton's law of cooling apply to putting a cold object in a warmer enviorment were it is actually getting warmer and not cooling down? If so is there a negative sign or no? This negative sign is bothering me and I'm unsure what to do for when the object is placed in a warmer enviorment and is actually heating up and not cooling down

thanks for any help

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# Homework Help: Newton's Law of Cooling of object

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