A metal rod of length 50cm is heated from 40oC to 80oC. If the linear expansivity of the material is \(\alpha\), calculate the increase in length of the rod (in metres) in terms of \(\alpha\)
A
20\(\alpha\)
B
200\(\alpha\)
C
2000\(\alpha\)
D
20000\(\alpha\)
Verified Correct Answer: A.
Physical Principles & Numerical Solution
\(L_2 - L_1 = \alpha_1 (\theta_2 - \theta_1) = \alpha \times 0.5 \times 40 = 20 \alpha\)
Source: Myschool Past Questions Archive (Record #35041)