# Newton's Law of Cooling

Physics

## definition

### Experimental verification of Newton's Law of cooling

Newton's Law of cooling can be verified with the experimental set-up shown in the figure. The set-up consists of a double walled vessel (V) containing water in between the walls. A copper calorimeter (C) containing hot water is placed inside the double walled vessel. Two thermometers through the corks are used to measure the temperatures of water in calorimeter and of hot water in between the double walls respectively. Temperature of hot water in the calorimeter is noted after fixed intervals of time. A graph is plotted between  and time(t). The nature of graph is observed to be a straight line having a negative slope which is in accordance of the equation of Newton's Law of cooling.

## definition

### Describe the limitations of Newton's Law of Cooling

The limitations of Newton's Law of cooling are as follows:
1. It can be used only at lower temperatures.
2. It can only be use when difference between initial and final temperatures is less than 50-80 degree Celsius.
3. It
holds true only if the temperature of the surroundings remains constant throughout the cooling of the body.

## definition

### Newton's Law of Cooling

Here, is time, is temperature of the object, and is the surrounding temperature.
Newton's Law of Cooling :
Newton's law of cooling states that the rate of cooling of an object is proportional to the temperature difference between the object and its surrounding.

## definition

### Assumptions of Newton's Law of Cooling

Assumptions of Newton's Law of Cooling are as follow :
1. Temperature difference between the object and surrounding should be small.
2. The nature of radiating surface should remain same.