0 2 4 6 8 10 120

2

4

6

8

10

12

14

16

Angular Velocity rad/s

Velocity m/s

This graph of tangential velocity vs. angular velocity for a point on a spinning disc, indicates that the point is what distance from the center of the disk?

STARTER

Starter

By what factor does the centripetal accelerationchange if the angular velocity is doubled?

Tripled?

Practice

Recall from the circular motion study that:

v =wr and ac = w2r

You will investigate these relationships.

Application : Circular Motion LabPart 1: v vs. w

Open “ Ladybug Revolution in phet physics simulations, online.

Go to Rotation tab.

Choose the following options: ( Close the q graph.)

Put the ladybug 2m from the center of the wheel.

Set w at 1,2,3,………………10 rad/sec and record v for each.

Plot v vs. w and get a fit.

Application : Circular Motion Lab Part 2 v vs. r

Open “ Ladybug Revolution in phet physics simulations, online.

Go to Rotation tab.

Choose the following options: ( Close the q graph.)

Set w at 2.00 rad/s and leave it there for all data.

Put the ladybug 1m from the center of the wheel. Start,and record v. Repeat for R = 2,3,and 4m.

Plot v vs. r and get a fit.

Application : Circular Motion Lab Part 3 : a vs. w

Open “ Ladybug Revolution in phet physics simulations, online.

Go to Rotation tab.

Choose the following options: ( Close the q graph.)

Put the ladybug 2m from the center of the wheel.

Set w at 1,2,3,………………10 rad/sec and record a for each.

Plot a vs. w and get a fit.

Data tablesPart 1  

w v

1.0  

2.0  

3.0  

4.0  

5.0  

6.0  

7.0  

8.0  

9.0  

10.0  

Part 2  

R v

1.0  

2.0  

3.0  

4.0  

Part 3  w a

1.0  2.0  3.0  4.0  5.0  6.0  7.0  8.0  9.0  

10.0  

Questions for the Lab

1. What is the slope of your v vs. w graph? What is the meaning of this number?

2. Is the a vs. w graph linear? What is the coefficient of the squared term? What is the meaning of this number?

3. How would your v vs. w graph have changed if you had placed the object

closer to the center of the rotating disk?

Lab Report Checklist

3 Data Tables

V vs. r graph with a curve fit

V vs. w graph with a curve fit

a vs. w graph with a curve fit.

Questions

Summary

Put this in your science notebook.

Exit

What do you expect the a vs. w graph to look like? Explain.