When a bar of length '$$l$$' and diameter 'd' is rigidly fixed at the upper end and hanging freely, then the total elongation produced in the bar due to its own weight is (where w = Weight per unit volume of the bar)

A $$\frac{{{\text{w}}l}}{{2{\text{E}}}}$$
B $$\frac{{{\text{w}}{l^2}}}{{2{\text{E}}}}$$
C $$\frac{{{\text{w}}{l^3}}}{{2{\text{E}}}}$$
D $$\frac{{{\text{w}}{l^4}}}{{2{\text{E}}}}$$

Correct Answer: $$\frac{{{\text{w}}{l^2}}}{{2{\text{E}}}}$$

Bissoy MCQ
#Mechanical Engineering #Strength Of Materials In ME

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