Question

An iron rod has a length of 50m when the temperature is 20°C. By how much will it expand when the temperature rises to 30°C? Take α = 1.2 × 10⁻⁵ , K⁻¹

a) 0.6 m
b) 0.3 m
c) 0.9 m
d) 0.15 m

Answer 1

The iron rod will expand by 0.6m when the temperature rises from 20°C to 30°C.

Step-by-step explanation:

The change in length of an iron rod can be calculated using the equation for linear thermal expansion, which is given by ΔL = αL0ΔT, where α is the coefficient of linear expansion, L0 is the initial length, and ΔT is the change in temperature. The iron rod will expand by 0.6m when the temperature rises from 20°C to 30°C. In this case, the initial length of the iron rod is 50m and the change in temperature is 30°C - 20°C = 10°C.

Plugging in the values, we get ΔL = (1.2 × 10^-5 K^-1)(50m)(10°C) = 0.006m = 0.6m.

Therefore, the iron rod will expand by 0.6m when the temperature rises from 20°C to 30°C.