DIRECTIONS: Run the Collision Lab at at http://phet.colorado.edu/en/simulation/collision-lab ( Don't download the app just click the Play button ], follow the instructions below , and answer the questions Make sure you are on the Intro tab and not the advanced tab (at the top)- SCENARIO 1: 100% Elastic collision between balls of equal mass DIRECTIONS: STEP 1: There is a green menu at right. Make sure the elasticity is set at 100%. There is a red ball and a green ball in the center of the screen. Make their masses equal by adjusting the tabs for mass below them . When you hit the play button Ball Mass below the two balls, the red ball will move towards the green ball and hit it in a perfectly elastic collision. 1. MULTIPLE CHOICE. Predict which of the following will happen after the red ball hits the green ball a. red ball and green ball will both move to the right at half the red ball's pre - collision speed. b. red ball and green ball will bounce off each other and head in opposite directions v with half red ball's pre -collision speed. c. red ball will hit green ball and bounce back with red ball's pre - collision speed . Green ball will not move d. red ball will stop in its tracks and green ball will move to the right with red ball's pre - collision speed 2. Run the simulation and see what happens. Were you right or wrong? O Right D Wrong STEP 2: Hit the reset button below the balls and the MORE Ball Mass Position Velocity Momentum DATA button so that you can see the mass, velocity, and 1.80 -0.75 position of the ball's before and after the collision. 050 How did they arrive at the momentum amount in the last column? In other words what is the formula for momentum ? (HINT: look at the units of momentum). STEP 3: Rerun the simulation. Fill in the data table below with the mass, velocity, and momentum BEFORE and AFTER the collision. Masses of the balls should be the same. Before Collision After Collision Velocity Momentum Velocity Momentum Ball Mass (kg ) (m/s) (kg *m /s) (m/s) (kg *m/s) 1 2 Total (Add Column 3 values ) What do you notice about the total momentum before and after the collision