Physics 1: Newton S Laws Note Outline

Pre-AP Physics Unit 3 Note Outline 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:

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

Pre-AP Physics Unit 3 Note Outline Linear Example: A car traveling initially at 20 m/s comes to a stop in a distance of 100 m. What was the acceleration?

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 2 s. What is the angular displacement?

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?