# Lab Activity: Inertia Stations

Time: 40 minutes. Most students had finished the stations and started on the paragraph by about 25 minutes.

I set up ten (10) inertia stations. I demonstrated each one or showed them what to do, and they had free range to move among them how they wished. They were instructed to write down what they did and what happened at each station. The final assignment was the write two paragraphs summarizing what they did, what they noticed, any patterns, and what this means for objects in motion or object at rest.

Station 1: Embroidery Hoop and Tennis Ball. Students use the embroidery hoop to get the tennis ball going in a circle. Eventually the tennis ball will pop out of the hoop. Observe the motion of the tennis ball after it leaves the hoop.

Station 2: 200g mass, 10 lb dumbbell, hammer. Hold the 200g mass carefully in your fist with about an inch sticking away from your hand and smack it on the end with the hammer. Notice how your hand moves. Pick up the dumbbell and hit it with the hammer. Notice how your hand moves.

Station 3: Mass vs Weight. 15 lb Dumbbell. Shake it up and down to feel the weight. Shake it side to side to feel the inertia.

Station 4: Stack of pennies. 10 pennies in a stack. Slide a penny at the bottom of the stack and see what happens. 10-11 is about the limit before the whole stack falls over due to friction between the bottom penny and the second to bottom penny. I thought huge stacks might be fun, but they didn’t work so well. I prefer to do this with washers, but I didn’t have any on hand.

Station 5: Mr. Squishy. Put Mr. Squishy on the cart and roll it toward the plank. Watch what happens when they hit. There’s a limit to how fast you can push the cart forward, too, so you see inertia in both cases. Almost anything reasonably light that stands up well would work.

Station 6: Cups and Coins. Flick the card and see what happens.

Station 7: TP of Science. Pull fast, pull slow, long tail, short tail, compare and contrast what happens.

Station 8: Flask (with cushioning of some sort at the bottom), quarter, embroidery hoop. Balance as shown above. Students try to snag the hoop out from under the quarter. Ideally the quarter goes in the flask. Some hoops are better for this than others, but you gotta trial and error it. There’s also a bit of a trick to it. I have maybe a 60% success rate when demonstrating for the first time, but you either get to wow them with your skills or model that it’s ok that things don’t always work the way you think they will or you want them to.

Station 9: Pulling the tablecloth from under the dishes. Pans have 1kg, 500g, 200g, and no extra weight. The 1kg mass was being used elsewhere when I took this picture. Students compare how the different masses affect pulling out the fabric. Note: flannel works as well as flat. I was surprised at this.

Station 10: (Not Pictured). Embroidery hoop and tennis ball. Students hold the tennis ball in their hand. Hoop goes on the ground. They walk, walk faster, and run across the room and attempt to drop the ball into the hoop. You have to make rules about not moving their arm so they don’t try to aim as they’re running. The goal is to realize that the faster they go, the earlier they have to release the ball.