A brass rod is .500 m long at 20.0celsius. what is the length of the rod if it is heated to 50.0 celsius

L' = 0.5002535 [m]

Explanation:

This is a characteristic problem of material mechanics, which includes deformation of an element by temperature increase.

In order to solve this problem, we need the value called the coefficient of thermal expansion and the use of the following expression:

DL = α*(DT)*L

where:

DL = Length change [m]

α = coefficient of thermal expansion [1/°C]

DT = Temperature change [°C]

L = Original length [m]

For copper or brass rod the α = 16.9*10^-(6) [1/°C]

DL = 16.9*10^-(6)*(50-20)*0.5

DL = 2.535*10^(-4) [m] = 0.0002535 [m]

The new length is:

L' = DL + L = 0.0002535 + 0.5 = 0.5002535 [m]

when jerome paddle in flowing river towards east the net speed of jerome will increase

so the net speed of jerome will be given as

now the speed of paul will be same as it is given as he is running on the ground

so

so here we can say since the speed of jerome is more so he will win the race

now as we know the distance so the time difference is given as

so jerome will reach first and the time difference will be 203.55 s or 3.4 min