Collision Lab.

PhET Collision Lab Directions: Go to the website http://phet.colorado.edu/en/simulation/collision-lab Make sure the 1-d box is checked. Part 1 Scenario #1: Elastic collision between balls of equal mass  Make a hypothesis about initial and final momentums before playing with the sim. Hypothesis: If the balls have equal mass then the initial and final momentum will have to bounce off of each other.  Make a data table for the following: mass, velocity and momentum of each ball before and after. Ball 1 Before After Mass 1.50 kg 1.50 kg Velocity 1.00 m/s -1.00 m/s Momentum 1.50 kg m/s -1.50 kg m/s Ball 2 Before After Mass 1.50 kg 1.50 kg Velocity -1.00 m/s 1.00 m/s Momentum -1.50 kg m/s 1.50 kg m/s  What is the relationship between the initial and final total momentums? The relationship between the initial and final total momentums is that they cancelled each other out and resulted it being in 0.  Describe the motion of the balls before and after the collision? After the balls collided with each other they bounced off and went in the opposite direc- tion. Scenario #2: Elastic collision between balls of unequal mass.  Make a hypothesis about initial and final momentums before playing with the sim. Hypothesis: If the balls have unequal mass then the initial and final momentums are go- ing to result in one ball moving while one stays.  Make a data table for the following: mass, velocity and momentum of each ball before and after. Ball 1 Before After

Mass 1.50 kg 1.50 kg Velocity 1.00 m/s -0.60 m/s Momentum 1.50 kg m/s -0.90 kg m/s Ball 2 Before After Mass 1.00 kg 1.00 kg Velocity -1.00 m/s 1.40 m/s Momentum -1.00 kg m/s 1.40 kg m/s  What is the relationship between the initial and final total momentums? The relationship between the initial and final total momentums for both balls is that they equal the same thing. When adding them up together, both balls equal 0.40 kg m/s.  Describe the motion of the balls before and after the collision? The ball with the heavier mass starts at the same velocity as the second ball but it starts to move slowly after it collides with the ball with less mass. The ball with less mass starts moving faster since the velocity was transferred. Part 2 Create 3 more distinct scenarios in 1-d including one totally inelastic collision. Make a hypothe- sis whether or not each will follow conservation of momentum. Collect some data and prove or disprove your hypothesis. Inelastic collision same mass Hypothesis: If the balls have the same mass, then nothing should change Ball 1 Before After Mass 1.50 kg 1.50 kg Velocity 0.50 m/s 0 m/s Momentum 0.75 kg m/s 0 kg m/s Ball 2 Before After Mass 1.50 kg 1.50 kg Velocity 0.48 m/s 0 m/s Momentum 0.72 kg m/s 0 kg m/s Different velocity Hypothesis: If they have different velocity then the balls should keep hitting/ bouncing off of each other. Ball 1 Before After Mass 1.50 kg Never-ending/keeps bounc- ing Velocity 3.00 m/s Never-ending/keeps bounc- ing Momentum 4.51 kg m/s Never-ending/keeps bounc-