Name: __________________________
Period: _____
Pre-AP Physics Unit 7: Angular Motion
Rotational Displacement:
Equation:
Definition of Radian
Example 1: A rope is wrapped many times around a drum of radius 50 cm.
How many revolutions of the drum are required to raise a bucket to a height of
20 m?
Example 2: A bicycle tire has a radius of 25 cm. If the wheel makes 400 rev, how far will the
bike have traveled?
Angular Velocity:
Equation:
Angular frequency:
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Pre-AP Physics Unit 3 Note Outline
Example 3: A rope is wrapped many times around a drum of radius 20 cm. What
is the angular velocity of the drum if it lifts the bucket to 10 m in 5 s? In the
previous example, what is the frequency of revolution for the drum?
Angular Acceleration
Equations:
Example 4: The block is lifted from rest until the angular velocity of the drum is 16
rad/s after a time of 4 s. What is the average angular acceleration?
Connecting Linear and Angular
Angular and Linear Speed:
Angular and Linear Acceleration:
A Comparison: Linear vs. Angular
Linear Example: A car traveling initially at 20 m/s comes to a stop in a distance of 100 m. What
was the acceleration?
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Pre-AP Physics Unit 3 Note Outline
Angular analogy: A disk (R = 50 cm), rotating at 600 rev/min comes to a stop after making 50
rev. What is the acceleration?
Example 5: A drum is rotating clockwise initially at 100 rpm and
undergoes a constant counterclockwise acceleration of 3 rad/s2 for
s. What is the angular displacement?
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On your own:
 Find the average angular velocity of a pitcher’s arm if, in throwing the ball, his arm rotates
one-third of a revolution on 0.1 sec.
 A turntable rotating at 33 1/3 rpm (0.56 rev/sec) is shut off. It brakes with constant angular
deceleration and stops in 26 seconds. Find the angular acceleration and the number of
revolutions it makes.
 The time required for a roulette wheel to coast to rest is 15 seconds. If the wheel completed
nine revolutions in this time what was the initial angular velocity?
 A bicyclist starts from rest and accelerates at 2 rad/sec2. In 10 seconds what is the angular
velocity of the bike wheels and how many revolutions has the bike wheels completed?
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