Complete question:
A scallop forces open its shell with an elastic material called abductin, whose Young's modulus is about 2.0×10⁶ N/m2 .
If this piece of abductin is 3.1 mm thick and has a cross-sectional area of 0.49 cm2 , how much potential energy does it store when compressed 1.5 mm ?
Answer:
The elastic potential energy of the material is 0.036 J
Explanation:
Given;
Young's modulus, E = 2.0×10⁶ N/m²
Thickness of the abductin, l = 3.1 mm = 0.0031 m
compression of the abductin, x = 1.5 mm = 0.0015 m
area, A = 0.49 cm² = 0.49 x 10⁻⁴ m²
Young's modulus for elastic material is given by;
[tex]E = \frac{stress}{strain} = \frac{Fl}{Ax} \\\\ E = \frac{F}{x}*\frac{l}{A}\\\\ E = k*\frac{l}{A}\\\\k = \frac{AE}{l}\\\\k = \frac{(0.49 x10^{-4})(2*10^6)}{0.0031}\\\\ k = 31,612.9 \ N/m[/tex]
The elastic potential energy of the material is given by;
U = ¹/₂kx²
U = ¹/₂(31,612.9)(0.0015)²
U = 0.036 J
Therefore, the elastic potential energy of the material is 0.036 J
