Topic: Strength of Materials
A round uniformly tapered bar of length L and Young's modulus E has diameter of 'd' at one end and '2d' at the other end. If the bar is pulled by an axial force F, the extension produced will be
- A. 2FL / (pi*E*d²)
- B. 4FL / (pi*E*d²)
- C. 8FL / (pi*E*d²)
- D. 16FL / (pi*E*d²)
Answer: A. 2FL / (pi*E*d²)
Explanation: Extension produced in a tapered bar is given by delta = 4FL / (pi * d1 * d2 * E). Substituting d1 = d and d2 = 2d yields delta = 4FL / (pi * d * 2d * E) = 2FL / (pi * E * d²).