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

Physics & Space Science

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