जब किसी पिंड पर दो परस्पर लंबवत प्रतिबल, σx और σy लगते हैं, तो मूल बिंदु से मोहर वृत्त (Mohr's circle) के केंद्र की दूरी कितनी होती 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: