10. An object is moving around a circle of radius 1.5 meters at a constant velocity of 7 meters per
second. The frequency of the motion, in revolutions per second, is
A. 0.24
B. 0.53
C. 0.67
D. 0.74
E. 0.98

acceleration = (change in speed) / (time for the change)

change in speed = (20-120)= -100 m/s.

1.5 min = 90 sec

acceleration = -100/90 = -1.11 m/s^2.

we don't care about the 150kg or the 2,500 meters. they don't make any difference.

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answera compound;

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