Newton’s Law of Cooling Validity – Rankers Physics

Newtons Law of Cooling: Practice Problem & Solution

Assertion (A): For small temperature difference between body and surrounding, the rate of cooling directly proportional to the difference in temperature, known as Newton's law of cooling. Reason (R): Newton's law of cooling is valid for heat transfer by radiation mode only.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Newtons Law of Cooling. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is the correct statement of Newton's Law of Cooling. Reason (R) is false, as the law applies to convection and can be approximated from radiation for small temperature differences, not exclusively for radiation.

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