Chapter U5.3, Problem 1E

Interpretation Introduction

Interpretation:

The reason due to which holding ice in hand feels cold needs to be explained.

Concept Introduction :

The energy contained in the motion and vibration of its molecules, is known as the thermal energy of an object.

A physical property of matter which quantitatively shows hot and cold is known as temperature.

Answer to Problem 1E

When a person holds an ice cube in hand, heat is transferred from warm hand to the cold ice and because of it ice starts melts. The person feels cold because the hand loses heat energy.

Explanation of Solution

When there are two objects and both are having different temperatures, heat will always flow from the warmer object to the colder object. Below are the three methods from which heat can be transferred:

1. Conduction − It is process of heat transfer from solids. Some of the substances like iron and copper are the good conductors compared to the other ones like paper and wood.
2. Convection − It is the process of heat transfer within the fluid occurred due to the movements of current. For e.g., gases and liquids increase in size once they are heated and decrease in size as they cool, forming circular convection currents.
3. Radiation − It is the process of energy transfer because of electromagnetic waves. Heat is transferred to an object once it will come in contact to electromagnetic waves.

So, when a person holds an ice cube in hand, heat is transferred from warm hand to the cold ice and because of it ice starts melts. The person feels cold because the hand loses heat energy. This is the conduction process.