Question

A wire of length L and area of cross-section A, is stretched by a load. The elongation produced in the wire is l. If Y is the Young’s modulus of the material of the wire, then the force constant of the wire is

• A. $\frac{YL}{A}$
• B. $\frac{Yl}{A}$
• C. $\frac{YA}{L}$
• D. $\frac{YA}{l}$

Answer 1

Answer: (C)

$\frac{YA}{L}$

Answer 2

: According to definition of Young’s modulus = 2.52 mm

$Y = \frac{F/A}{l/L}$

$\therefore F = \frac{YAl}{L}$

Force constant $= \frac{F}{l} = \frac{YA}{L}$