ch08-p018 - 18. We place the reference position for...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
18. We place the reference position for evaluating gravitational potential energy at the relaxed position of the spring. We use x for the spring's compression, measured positively downwards (so x > 0 means it is compressed). (a) With x = 0.190 m, Eq. 7-26 gives 2 1 7.22 J 7.2 J 2 s Wk x =− ≈− for the work done by the spring force. Using Newton's third law, we see that the work done on the spring is 7.2 J. (b) As noted above,
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.
Ask a homework question - tutors are online