(light music) – Welcome to Conservation: It’s the Law! In this activity you’re going to explore two of the most powerful laws in all of science — The law of conservation of momentum and the law of conservation of energy. So let’s take a look at your supplies. First, make sure you have the activity guide and it has data tables and questions for you to record your observations. Now you have a piece of track that you need to support on one end using some books or a wall. Make sure you tape your track down, so it’s nice and stable. You’re gonna need seven marbles, all of equal mass and size. Then you’re going to need to measure out your release heights for the marbles. Notice we have five, 10 and 15 centimeters. It needs to be measured straight up from the table. And when you release it, you’re gonna look very closely to what happens during the collision. You’re gonna look at how many marbles actually come out the other end. So if I have one marble that’s colliding in front, how many marbles are going to take off at this end? Then you’ll increase it to two marbles, three marbles and four marbles. Each at five, 10 and 15 centimeters. The second thing you’re gonna look at in the next data table is the speed before the collision and after the collision of the marbles. So you can’t really measure the speed so we’re just going to do qualitative observation. So for instance, a low speed would be say from five centimeters, there’s your low speed. So that would be your incoming speed. What’s going to be the outgoing speed of the marble or marbles that take off afterwards, OK? Is it going to be slow, medium or fast? So you’re gonna be studying a lot of collisions here. Have fun.