Question

A shaft of circular cross section (diameter = 3 in) is subjected to a bending moment of 3200 lb- ft. Determine the bending stress at the surface of the shaft.

Answer 1

`\sigma =145.62 MPa`

Step-by-step explanation:

Given that

Diameter of shaft=3 in (1 in=0.0254 m)

Bending moment=3200 lb-ft (1 lb-ft=1.35 N-m)

We know that bending stress in circular shaft given as

`\sigma =(32M)/(\pi d^3)`

Where M is the bending moment and d is the diameter of shaft.

Given that M=4338.61 N-m

d=0.0672 m

Now by putting the values

`\sigma =(32* 4338.61)/(\pi * 0.0672^3)`

So
`\sigma =145.62 MPa`