A 12 m long bar when heated from 20 degc to 70 degc becomes

Question

1. A 12 m long bar, when heated from 20 °C to 70 °C, becomes 12.008 m long. Calculate the linear expansion coefficient of that bar.

2. The Linear expansion coefficient of steel is 11*10^-6 °K^-1. If a cube of steel, with side length 4 m, is heated by 120 °K, what will be its new volume?

3. Given the ideal gas law PV = nRT with R = 8.3 J/(°K*mol), calculate the volume of one mol of air at 20 °C and 1*10⁵ Pa. (Warning: in the equation, T is expressed in Kelvin).

4. Given the two temperatures T₁ = 40 °C and T₂ = 80 °C, first convert them into °K thencalculate the three quantities:  T₁ - T₂  ;   T₁ / T₂   ;   ln(T_1/ T₂); (the last is the natural logarithm).