Question

A bimetallic strip is consisting of metals X and Y. It is found to be mounted rigidly at the base as represented in the diagram. The coefficient of the linear expansion of X will be higher than that of Y. What will happen when the bimetallic metal stand is kept in a cold bath?

A. it will bend towards the right
B. it will bend towards the left
C. it will not shrink
D. it will neither bend or sink

Answer 1

Hint: The coefficient of Linear Expansion is the rate of variation of unit length per unit degree variation in temperature. The linear expansion coefficient will be an intrinsic characteristic of every material. Therefore it will be changing from one material to another. This will be helpful in answering this question.

Complete step by step answer:
As the metal X is having a higher coefficient of the linear expansion compared to metal Y. Therefore, on placing the bimetallic metal will be standing in a cold bath, X would be shrinking more than Y. Thus the strip will be bending towards the left. When the bimetallic metal stand is kept in a cold bath it will bend towards the left.

So, the correct answer is “Option B”.

Note: Expansion is defined as the variation or increase in the length. When the variation in length is along one dimension, that is, length over the volume, then it is known as the linear expansion. The primary reason for this expansion will be the variation in temperature. Therefore the variation in temperature will be reflected in the rate of expansion. It is how much the material can overcome its original shape and the size by the influence of heat radiation is defined using this concept.