Question

How much will the length of a 2 m long rod increase by 100 degree C? (Provided, alpha = 0.000012 per degree Celsius).

Answer 1

Answer:

Free expansion of the rod =αLΔθ

=15×10  

−60

C×2m×(50−20)  

0

C

=9×10  

−

4m=0.9mm

If the expansion is fully prevented, then

Strain=  

2

9×10  

−4

 

​  

=4.5×10  

−4

 

Temperature Stress = Strain ×Y

=4.5×10  

−4

×2×10  

11

=9×10  

7

N/m  

2

 

If 0.4  mm expansion is allowed, then length restricted to expand

=0.9−0.4=0.5mm

Strain=  

2

5×10  

−4

 

​  

=2.5×10  

−4

 

Temperature stress = Strain ×Y=2.5×10  

−4

×2×10  

11

=5×10  

7

N/m  

2

Explanation:

Hope this example helps you