Question

A sign (mass 2500 kg ) hangs from the end of a vertical steel girder with a cross-sectional area of 0.014 m2 . Ignore the mass of the girder itself. The elastic modulus for steel is 2.0×1011N/m2.

What is the stress within the girder?

What is the strain on the girder?

If the girder is 8.50 m long, how much is it lengthened?

Answer 1

Given is:-

mass

Cross sectional area  

Elastic modulus of steel is  

Now,

part - 1

Stress is given by

or

by plugging all the values we get

which gives us

Part - 2

Strain is given by

thus

which gives us

Part - 3

We know that

by plugging all the values we get

which gives us