Answer 1

Original length, I = 10 cm = 0 .1 m Rise in temperature, t = 30 - 20 = 10°c Coefficient of linear expansion, a = 1. 7 x 10^-5°C ^-1
Increase in length = I x t x a
= 0 .1 x 10 x 1. 7 x 10^-5
= 1.7 x 10^-5m