A 1.2-kg mass is projected up a rough circular track (radius = 0.80 m) as shown. The speed of the mass at point A is 8.4 m/s, and at point B, it is 5.6 m/s. What is the change in mechanical energy between A and B caused by the force of friction?
a.
?2.7 J
b.
?8.8 J
c.
?4.7 J
d.
?6.7 J
e.
?19 J
c
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