I think I understand a & b... but how do I get c? Let me know if my answers for
ID: 2183120 • Letter: I
Question
I think I understand a & b... but how do I get c? Let me know if my answers for the first 2 are correct. Curve A (the leftmost curve in the diagram below) is a plot of the gravitational force as the masses are added vs. the displacement of the hanger. Curve B (the rightmost curve below) is a plot of the gravitational force as the masses are removed vs. the displacement of the hanger.The absolute the value of the area under curve A is 1.261 J. The absolute value of the area under curve B is 1.077 J.
(a) The sign for work done by gravity as the masses are added (represented by curve A) should be .
My A: +
(b) Wnet done by gravity = J.
My A: W1+W2
1.261+ -1.077
= .184 J
(c) How much energy was lost? J
Explanation / Answer
Work done by gravity should be equal to area-under force displacement curve. Now the question is which area to choose. Net work done by gravity= Total area of the two curves as gravity is doing work in both cases =1.252 J+1.013 J =2.265 J Energy lost=Area between the two curves=1.252 J-1.013 J = 0.239 J