Question

The dimensions of four wires of the same material are given below. In which wire the increase in length will be maximum when the same tension is applied

• A. Length 100 cm, diameter 1 mm
• B. Length 200 cm, diameter 2 mm
• C. Length 300 cm, diameter 3 mm
• D. Length 50 cm, diameter 0.5 mm

Answer 1

Answer: (D)

Length 50 cm, diameter 0.5 mm

Answer 2

If same force is applied on four wires of same material then elongation in each wire depends on the length and diameter of the wire and given by $l \propto \frac{L}{d^{2}}$ and the ratio of $\frac{L}{d^{2}}$ is maximum for (4) option.