Question

A wire of length 100 cm increases in length by ${10}^{-2}$ m when it is heated through ${100}^{\circ }C$. The coefficient of linear expansion of the material of the wire expressed in /K units is :

• A. $-1\times {10}^{{}^{-6}}/K$
• B. $1\times {10}^{{}^4}/K$
• C. $1\times {10}^{{}^{-4}}/K$
• D. ${10}^{{}^{-2}}/K$

Answer 1

The correct option is C $1\times {10}^{{}^{-4}}/K$

In case of temperature difference, the value in degree centigrade is same as in degree kelvin. Initial length $=$ 1m. Change in length $=$ ${10}^{-2}m,$ change in temperature $=$ 100 kelvin. Putting these values we get $\alpha$ $=$ 1 X ${10}^{-4}/$K