Q. Assertion: Girders are given I shape.
Reason: To bear more pressure, depth is increased as per .

 497  150 Mechanical Properties of Solids Report Error

Solution:

The most effective method to reduce depression in a beam of given length & material is to make depth of the beam large as compared to its breadth. But on increasing the depth too much, the beam bends. To check this buckling, a compromise between breadth & depth of a beam is made by using I-shaped girder.