Every wonder why you have to wear a seat belt or wear a helmet? Let's find out (safely) by experimenting with a ball.You will need to find:
- a car
- a licensed driver
- a ball
2. Sit in the back seat and put the tennis ball in the seat next to you.
3. Now watch the ball carefully as the car moves. See how it moves around the seat? (Try not to let it get on the floor and roll around. It might roll under the pedals and that would be bad.)
4. Pretty easy huh? As the car moves forward at 20 mph, everything in the car is moving forward at 20 mph. Everything in the car has the same inertia. If the car were to stop suddenly, everything in the car that’s not bolted down, still moves forward at 20 mph until it hits something. An object at rest tends to stay at rest, an object in motion tends to stay in motion. Right? So, if the car stops quickly, the tennis ball continues to move forward until it hits something. If the car turns, the ball continues to go in the direction it was going a second ago, so it rolls around the seat. What would happen if the car stopped suddenly and you weren’t wearing a seat belt? Yup, you’d fly forward at whatever speed the car was going until you crashed into something in the car. See now why seat belts are your best friend?
Download Student Worksheet [/am4show]
We actually just got home from running errands and I saw this video… It made me laugh because I had a water bottle in the car with me. (I had set it on the floor) I enjoyed watching it rock (and fall) back and forth when the car stopped and went forward. THANKS!
Mine also went backwards is that normal?
how do we get the stuff? it says we don’t have access.
thanks for being so nice
that sounds fun
have a good day :)(:
Most of our experiments have video… this one was so simple that we didn’t make a video. Let me know if you need help with a specific part of the activity.
wheres the vidio