The length of an aluminium bar of length 80 cm increases by 1 mm on heating.What is the final temperature of the bar if it was initially at temperature 20 degree Celsius? (coefficient of linear expansion of aluminium =25*10-6/degree Celsius)

Answer 1

change in L/L = 25*10^-6 (T-20)

.1/80 = 1/800 = 25* 10^-6 (T-20)

T-20 = 10^6/2*10^4 =50

T = 70 deg C