Question

A metal wife of length L area of cross section A and Young modulus Y is streched by a variable force F such that F is always slightly greater than the elastic forces of resistance in the wife when the elongation of the wire is $\phi$ then correct option(s)

• A. the work done by F is $\frac{1YA}{2L}{\phi }^2$
• B. The elastic potential energy stored in the wire is $\frac{1YA}{2L}{\phi }^2$
• C. no heat is produced during the elongation
• D. the work done by if F is $\frac{1YA}{L}{\phi }^2$

Answer 1

Answer: (A), (B), (C)

The correct options are
A the work done by F is $\frac{1YA}{2L}{\phi }^2$
B The elastic potential energy stored in the wire is $\frac{1YA}{2L}{\phi }^2$
C no heat is produced during the elongation