बाहरी बेंडिंग मोमेंट (bending moment) के कारण किसी संरचनात्मक अवयव में उत्पन्न होने वाले आंतरिक प्रतिरोधी प्रतिबल को क्या कहा जाता है?

When a bar of length l and uniform cross-section is rigidly fixed at the upper end and hangs freely, the total elongation produced in the bar due to its own weight is given by (where w = weight per unit volume and E = Modulus of Elasticity):

The hoop stress set up in a thin cylinder subjected to internal fluid pressure is: