Question
Question: A spring of spring constant \(5 \times 10 ^ { 3 } \mathrm {~N} / \mathrm { m }\) is stretched initia...
A spring of spring constant 5×103 N/m is stretched initially by 5 cm from the unstretched position. Then the work required to stretch it further by another 5 cm is
A
6.25 N-m
B
12.50 N-m
C
18.75 N-m
D
25.00 N-m
Answer
18.75 N-m
Explanation
Solution
Work done to stretch the spring from x1 to x2
W=21k(x22−x12)
=215×103[(10×10−2)2−(5×10−2)2] =21×5×103×75×10−4=18.75 N.m