In this lesson students will use a NetLogo model to analyze the effects of car mass, car speed, %elasticity, and time of collision on the impulse and acceleration experienced by the cars in a 1-Dimensional collision.
Students will also alter those variables to determine the maximum impulse and g's of acceleration that can be experienced in a collision given the limits on the variable values provided here.
Finally students will determine the effect of time of collision on the g's of acceleration experienced by an individual car.
The NGSS standard: HS-PS2-1 Motion and Stability: Forces and Interactions
Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration.
The NGSS standard: HS-PS2-2 Motion and Stability: Forces and Interactions
Use mathematical representations to support the claim that the total momentum of a system of objects is conserved when there is no net force on the system.
Unit designed by Neil Schmidgall a teacher at Glenbrook South.
You will use a NetLogo model to analyze the effects of car mass, car speed, %elasticity, and time of collision on the impulse and acceleration experienced by the cars in a 1-Dimensional collision.
You will also alter those variables to determine the maximum impulse and g's of acceleration that can be experienced in a collision given the limits on the variable values provided here.
Finally you will determine the effect of time of collision on the g's of acceleration experienced by an individual car.
A NetLogo collision involving 2 sets of cars (Car0 collides with Car2 and Car1 collides with Car3) is set up in order to compare the effects of mass, speed, %elasticity, and time of collision on the impulse and acceleration of the cars. The only difference in the 2 collisions relating to the individual cars is the mass and/or speed of Car0 compared to Car1. You can also set a difference between the top and bottom collisions regarding %elasticity using the 
slider. Experiment with the sliders below in order to become familiar with the modeling environment. Click on setup and go to run the model.
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Cars in Collision |
Slider for Car0 |
Slider to increment Car0's value for Car1 |
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The slider control as well as the before and after situation of a perfectly inelastic collision involving equally massed cars is shown below comparing different initial speeds of Car0 versus Car1. This setting puts Car0's velocity at 30 and Car1's velocity at 40.
Perform this collision with the masses and initial velocities as shown in the table below. Fill in the remaining cells in order to quantify this situation where each car is its own system. Keep the COE slider at 0%. Set the speed and time sliders of the collision as below:
Set the following masses and velocities for testing.
How did an increase in speed affect the impulse on the cars during the collision?
How did an increase in speed affect the g’s of acceleration the cars experienced during the collision?
Perform this collision with the masses and initial velocities as shown in the table below. Fill in the remaining cells in order to quantify this situation where each car is its own system. Set the %elasticity and time sliders of the collision as below:
Set the following masses and velocities for testing.
How did an increase in %elasticity affect the impulse on the cars during the collision?
How did an increase in %elasticity affect the g’s of acceleration the cars experienced during the collision?
Perform this collision with the masses and initial velocities as shown in the table below. Fill in the remaining cells in order to quantify this situation where each car is its own system. Keep the COE slider at 0%. Set the mass and time sliders of the collision as below:
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Set the following masses and velocities for testing.
How did an increase in mass affect the impulse on the cars during the collision?
How did an increase in mass affect the g’s of acceleration the cars experienced during the collision?
Using what you found out from the collisions above create scenarios that maximize the impulse on at least one car. Alter mass, mass increment, speed, speed increment, %elasticity, %elasticity increment, and time of collision in order to do so:
Maximum Impulse on at least one car should be at least 1080 N*s.
Using what you found out from the collisions above create scenarios that maximize the g’s of acceleration experienced by at least one car. Alter mass, mass increment, speed, speed increment, %elasticity, %elasticity increment, and time of collision in order to do so:
Maximum g’s of Acc of at least one car should be at least 137.76 g's. That is a lot of g's!
Using your setup from Question 2.11, alter only the time to its maximum value. How much did increasing the time of impact affect the g's of acceleration? What does this say about the importance of an airbag in modern cars?
