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2.1In-ClassAssignment.docx

Name: ______________________ Date turned in: ____________________

Name:

If you arrived late, had to leave early, or missed the lab entirely, indicate the reason below.

Supplemental Lab 2-1: Impulse, Momentum, and Collisions

Due at end of class.

Part 1 Impulse Equals Change in Momentum

Open the simulation for the Impulse Lab Simulation (see Canvas)

https://www.thephysicsaviary.com/Physics/Programs/Labs/ImpulseLab/

This simulates an astronaut (Wally) firing a fire extinguisher to propel him toward a pair of photogate timers. The simulation will keep track of how long the force was applied and the photogates and timer will allow you to calculate the speed achieved. Then we will calculate impulse and momentum to see if the Impulse equals the Change in Momentum.

Click on the box that says Begin.

Use the green arrows to Adjust the Extinguisher Force to 190 N.

Use the red arrows to adjust Wally’s mass to 90 kg.

Click Activate and watch as the astronaut accelerates toward the photogates (red lines at left).

Click Shut off before 4000 ms for best results. After shutting the force down, he will coast at a constant speed until he triggers the timer at the first photogate and shuts the timer off at the second photogate. [Be sure to shut off the force well before he reaches the red lines.]

The photogates are 10.000 meters apart.

Note that the time units are ms which stands for milliseconds. There are 1000 milliseconds in 1 second.

Record the results next:

Photogate Time = Click or tap here to enter text.

Force Time = Click or tap here to enter text.

Convert the times in milliseconds to seconds by dividing each time by 1000. Record the times in standard units below.

Photogate Time = Click or tap here to enter text. [Use this time to calculate the velocity.]

Force Time = Click or tap here to enter text. [Use this time to calculate Impulse.]

Calculate his velocity using the formula Click or tap here to enter text.

Now calculate Impulse = force x time = _____________ x _____________ = Click or tap here to enter text.

Finally calculate Momentum = mass x velocity = ______________ x ___________ = Click or tap here to enter text.

Impulse should equal the Change in Momentum.

The two numbers won’t be exactly equal but they should be close.

Part 2 Momentum and Kinetic Energy in Collisions

Open Collision Lab Simulation (Link on Canvas): https://www.physicsclassroom.com/Physics-Interactives/Momentum-and-Collisions/Collision-Carts/Collision-Carts-Interactive

Enter a value for Mass of Car 1 (1kg, 2kg or 3kg)

Enter a value for Mass of Car 2 (kg)

Enter a value for the Velocity of Car 1 between +1 and +10 m/s.

Enter a value for the Velocity of Car 2 between 0 and –10 m/s (and not the same speed as used for Car 1).

Record these values in the Table below and use them to calculate each car’s initial momentum and kinetic energy.

Initial Conditions

Before Collision

Mass

Velocity

Momentum

Kinetic Energy

Car 1

Car 2

Total

First Set the button for a totally elastic collision.

Run the simulation and pause it after the collision. Record your new velocity values and re-calculate momentum and kinetic energy. Record your values in the table below.

Elastic Collision

After Collision

Mass

Velocity

Momentum

Kinetic Energy

Car 1

Car 2

Total

Click Restart and click over to the button for an inelastic collision in which the cars stick together after impact. Run the simulation and pause after the collision. Record your new values for velocity, momentum, and kinetic energy.

Inelastic Collision

After Collision

Mass

Velocity

Momentum

Kinetic Energy

Car 1

Car 2

Total

Answer the following questions based on the data collected:

For the elastic collision was momentum conserved (yes or no)? Click or tap here to enter text.

For the elastic collision was kinetic energy conserved (yes or no)? Click or tap here to enter text.

For the inelastic collision was momentum conserved (yes or no)? Click or tap here to enter text.

For the inelastic collision was kinetic energy conserved (yes or no)? Click or tap here to enter text.

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