Concepts of Physics

IIT JEE Physics (1978-2018: 41 Years) Topic-wise Complete Solutions

The feeling of hotness not only depend on temperature!

Objective

To understand the factors that affect the amount of heat absorbed.

Introduction

The hotness of different substances varies even when they are at same temperature. While visiting temples in hot summer, we feel comfortable to walk over the footpath covered with carpet made of jute etc. Why it is so?

Apparatus

a \(4''\) by \(4''\) piece of cloth, metal plate

Procedure

Place one of your hand over the cloth and other on the metallic plate. You will feel that metal plate is colder although both the material are at the same room temperature.

Discussion

A metal plate is a better conductor of heat than the cloth. Normally, body temperature is more than the outside temperature. When you touch both the objects with two hands the metal takes away heat from your body quickly as compared to that by the cloth. Because of this, your hand feels the metal cooler than the cloth.