A typical CD will spin up from rest to about 500 rpm in about 3.0 s. The CD has a mass of 15.6 g and a radius of about 6.0 cm. What is the average torque on the CD

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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50 inches should be the resultant vector

the total distance that martina travels that day is

(distance from home to mom's office) plus (distance from mom's office to school)

plus (distance from school to library) plus (distance from library to friend's house)

plus (distance from friend's house to martina's house).

(we don't know what any of these distance actually is.)

that would be because of both gravity and friction. so     c