Name_________________________________________ Date_____________

Projectile Motion:   cannon

Site 2: http://phet.colorado.edu/simulations/   -- click on projectile motion link -- click on “run now”

Simulation tips: 

The square yellow box can be used to measure distance.
If you need to reset simulation to its original starting points, enter these value: Angles = 80; Initial speed = 18; mass =2, diameter =.1.

You can see the range, height and time in the top boxes.

Instructions:  Answer these questions by changing the variables.   Remember it is best to change only one variable (the one you are testing) and leave the others constant.

Question 1:   If you cut the projectile’s velocity in half, will the range also be cut in half.  Show your data below. (Make sure air resistance is not checked.)

Choose ONE projectile to test: Golf Ball checkbox Bowling Ball checkbox Pumpkin checkbox Adult Human checkbox
Velocity

4 m/s

8 m/s

16 m/s

32 m/s

64 m/s

Range


 

 

 

 

Answer to Question 1:

 

 

Graph the data. Place velocity on the X axis and Range on the Y axis

 

Question 2: How does air resistance affect these distances?

 

Range; Launch at 18 m/s and Angle 60 degrees

 

No Air Resistance 

With Resistance (check box)

Tank shell

 

 

Golf ball

 

 

Baseball

 

 

Bowling Ball

 

 

Football

 

 

Pumpkin

 

 

Adult Human

 

 

Piano

 

 

Buick

 

 

Answer to Question 2:

 

Based on the data you gathered (above), complete the set of sentences?

a. Objects that are round, like baseballs and golf balls will travel [ farther | not as far | the same distance ] if there is air resistance.

b. Objects that are shaped like a bullet, like the tankshell will travel [ farther | not as far | the same distance ] if there is air resistance.


Question 3:  What angle, speed and mass can be used to hit the target? 

Place your target so that it is exactly 20 meters from the cannon. Use any angle, velocity, or object to hit the target. When you are successful, indicate on the table below the combinations that work.

There are several answers here; you just need to find three that work.

 

Angle

Speed

Mass (object)

Target Hit 1

 

 

 

Target Hit 2

 

 

 

Target Hit 3