Question

Question 39:
For a circular cross section of a beam if
Imax = 20 MPa at N.A. then qaverage will be
10 MPa
20 MPa
30 Mpa
15 MPa​

Answer 1

Therefore the average stress at the Neutral Axis of the circular cross-section ( σavg ) is 15 MPa.

Given:

The maximum stress at the Neutral Axis of the circular cross-section = σmax = 20 MPa

To Find:

The average stress at the Neutral Axis of the circular cross-section ( σavg )

Solution:

The given question can be solved using this simple approach as shown below.

The maximum stress at the Neutral Axis of a circular cross-section = σmax = 20 MPa

In the circular cross-section,

⇒ σmax = ( 4σavg ) / 3

⇒ σavg = ( 3σmax ) / 4

⇒ σavg = ( 3 × 20 ) / 4 = 15

Therefore the average stress at the Neutral Axis of the circular cross-section ( σavg ) is 15 MPa.

#SPJ1