A wire, 20m long is heated from a temperature of 5°C to 55°C. If the change in length is 0.020m, calculate the linear expansivity of the wire
1.0 x 10-3k-1
2.0 x 10-4k-1
2.0 x 10-5k-1
1.0 x 10-5k-1
2.0 x 10-6k-1
Correct answer is C
\(\alpha = \frac{\Delta L}{L \Delta \theta} = \frac{0.020}{20 \times (55 - 5)} = 2.0 \times 10^{-5}\)