JEE Main 2026 Physics question
A copper wire of length 3 m is stretched by 3 mm by applying an external force. The volume of the wire is 600×10⁻⁶ m³. The elastic potential energy stored in the wire in stretched condition would be J. (Given Young modulus of copper = 1.1×10¹¹ N/m²)
Answer: 33
Solution
strain=0.003/3=10⁻³. PE=½Y(strain)²V=½(1.1×10¹¹)(10⁻⁶)(600×10⁻⁶)=33 J.