Question

If a simply supported beam AB of span 6 m is subjected to a concentrated load of W acting at a distance of 2 m from the left support A, then

• A. maximum bending moment occurs at the support A.
• B. maximum shear force occurs at support B.
• C. maximum bending moment occurs at the centre.
• D. maximum bending moment occurs under the load.

Hint:

Remember this critical rule: Maximum bending moment occurs where shear force is zero.
For a simply supported beam with only point loads, the SFD is a series of horizontal lines.
The shear force will change sign at one of the load points, and that's where the BMD will have its peak.

Answer 1

The Correct Option is D

Step 1: Understanding the Question:
Simply supported beam with single off-center point load. Where is max BM?

Step 2: Key Principle (Alternate):
Maximum bending moment occurs where shear force is zero or changes sign.

Step 3: Detailed Explanation:
SFD: constant positive from left support to load, drops at load, constant negative from load to right support. SF changes sign exactly at the load point. Therefore max BM occurs directly under the concentrated load.

Step 4: Final Answer:
Maximum BM occurs at the point of application of the load.