Question
Physics Question on work, energy and power
When a rubber -band is stretched by a distance x, it exerts a restoring force of magnitude F=ax+bx2, where a and b are constants. The work done in stretching the unstretched rubber-band by L is :
A
aL2+bL3
B
21(aL2+bL3)
C
2aL2+3bL3
D
21(2aL2+3bL3)
Answer
2aL2+3bL3
Explanation
Solution
∫dW=∫F⋅dl
W=∫0Laxdx+∫0Lbx2dx
=2aL2+3bL3