Question

What is length of a steel bar in Arizona (42^oC) if its length in North Dakota is 200 m? (Temperature in North Dakota is 7^oC).

Answer 1

Change in length due to temperature is given by,

dL = L0*alpha*dT

here, L0 = length of rod in Arizona = 200 m

alpha = thermal expansion Coefficient of Steel = 1.2*10^-5 1/K (Check this value in your reference book)

dT = Tf - Ti = 42 - 7 = 35 C

Tf = final temperature in Arizona = 42 C

Ti = Initial temperature in North Dakota = 7 C

So,

dL = L - L0 = L0*alpha*dT

L = length in Arizona = L0*(1 + alpha*dT)

L = 200*(1 + 1.2*10^-5*35)

L = 200.084 m

Let me know if you've any query.

answered by: anonymous