Student Exploration: Air Track
Directions: Follow the instructions to go through the simulation. Respond to the questions and
prompts in the orange boxes.
Vocabulary: air track, approach velocity, conservation of energy, conservation of momentum, elasticity, kinetic
energy, momentum, separation velocity, velocity
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
Imagine going to a bowling alley with a bowling ball and a ping pong ball.
1. Why is a bowling ball better for knocking down pins than a ping pong ball?
It has more mass and can knock the pins down with more force than a ping pong ball.
2. Which do you think would knock down more pins, a bowling ball moving 10 meters per second or a bowling
ball moving 10 centimeters per second?
A bowling ball moving 10 meters per second would knock down more pins.
3. What two factors seem to most affect the amount of damage that occurs in a collision?
Speed and mass.
Gizmo Warm-up
An air track is a device that helps scientists study motion. Air
comes out of holes in the track, allowing the gliders to move
with minimal friction.
1. On the Air Track Gizmo, click Play ( ) to view a collision between the two gliders. What do you see?
They knock into each other then separate again
2. Click Reset ( ). The velocity (v) of an object describes its speed and direction. The velocity of each
glider is indicated next to the v1 and v2 sliders. Click Play, and then click Pause ( ) just before the
collision.
A. What is the velocity of Glider 1? 5 m/s
B. In which direction does Glider 1 move? right
C. What is the velocity of Glider 2? -5 m/s
D. In which direction does Glider 2 move? left
Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved
, Activity A: Get the Gizmo ready:
● Click Reset.
Momentum
Question: How does an object’s momentum change when it collides with another object?
1. Explore: The Gizmo allows you to adjust the mass and initial velocity of each glider. Set up each of the
following scenarios, and describe what happens when the gliders collide.
A. The gliders have the same mass but different velocities.
The glider with a higher velocity had a higher momentum before the collision but a lower
momentum after.
B. The gliders have the same mass and one glider is stationary.
The stationary glider had a momentum of zero before the collision and had a higher
momentum than the glider that was moving after the collision.
C. The gliders have the same speed (but moving in opposite directions) and different masses.
The glider with more mass had less momentum after the collision while the glider with less
mass switched from having less momentum to having more.
2. Calculate: An object’s momentum (p) describes how hard it is to stop. Momentum is equal to the product
of mass and velocity: p = mv. If mass is measured in kilograms and velocity in meters per second, the unit
of momentum is kilograms-meters per second, or kg•m/s.
A. What is the momentum if the mass is 1.5 kg and the velocity is 4 m/s? 6 kg * m/s
Turn on Show numerical data and use the Gizmo to check your answer.
B. How could you use the Gizmo to increase a glider’s momentum?
I could increase the gliders momentum by increasing either the mass or speed of the glider.
3. Gather data: Click Reset. Set m1 to 3.0 kg and v1 to 2.0 m/s. Set m2 to 2.0 kg and v2 to
-4.0 m/s. Fill in the left table, run the collision, and then fill in the right table.
Before collision After collision
Glider Glider 1 Glider 2 Glider Glider 1 Glider 2
Mass 3.0 kg 2.0 kg Mass 3.0 kg 2.0 kg
Velocity 2.0 m/s -4.0 m/s Velocity -2.8 m/s 3.20m/s
Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved