For the rotational part of the experiment, a student measures a force of 1.8 n when the radius is 12 cm and the angular velocity 10 rad/s. a. what is the total mass of the object undergoing uniform circular motion? b. if the same mass (at the same radius) is rotated at 5 rad/s, what will be the measured force?

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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the motion of a pendulum is a classic example of mechanical energy conservation. a pendulum consists of a mass (known as a bob ) attached by a string to a pivot point. as the pendulum moves it sweeps out a circular arc, moving back and forth in a periodic fashion.