A metal rod of length 40cm at 20°C is heated to a temperature of 45°C. If the new length of the rod is 40.05cm. Calculate its linear expansitivity
-
A.
1.2 x (10^{-5}K{-1}) -
B.
2.5x (10^{-5}K{-1}) -
C.
3.5x (10^{-5}K{-1}) -
D.
4.5x (10^{-5}K{-1}) -
E.
5x (10^{-5}K{-1})
Correct Answer: Option E
Explanation
(alpha = frac{I_2-I_1}{I_1(theta_2-theta_1)} \ Rightarrow frac{40.05 – 40}{40 times (45-20)} = 5.0 times10^{-5})