Water Balloon Toss
Materials:
Several water balloons
Two people who don’t mind getting wet!
Directions:
Begin with one balloon and face your friend. Toss the balloon. If your friend catches is successfully, both of you take one step away from each other.
Continue until the balloon bursts.
Science Drops:
The balloon forms a protective skin around the water. If the balloon lands on something soft, it won’t burst. As long as there is a little give – whether it is because of your soft hands moving backwards to catch the balloon or soft grass – it slows down the impact and protects the water inside. If the balloon lands on something hard, like concrete, it bursts!
Football players wear helmets and pads to protect themselves from hard hits in the games. Bicyclists wear protective elbow and knee pads. The helmets and pads provide the soft protection than the balloon provides the water.
In the Car
Materials:
A car
An adult willing to drive it
Directions:
Ask the adult to drive somewhere so that you can make several turns at different and safe speeds.
How do you feel when the car is turning? Are you getting pushed into the door? What happens when you turn a corner at a fast speed? Is this a different feeling from making the turn at a slow speed?
Science Drops:
You aren’t actually getting pushed into the door. You can blame it on your inertia. Your body is moving in a straight line, and wants to stay moving in a straight line. (Sir Isaac Newton first described the Law of Inertia.) When the car turns, its inertia is changing, so the car is actually pushing in to you!
You can also try this experiment with a helium balloon. Since helium is lighter than air, it has very little inertia. If you held onto the helium balloon while turning the corner, the balloon will continue in a straight line. (Because of this, helium balloons can be dangerous to drive with. If you do this experiment, be certain that someone is holding onto the balloon, and can pull it into their laps, if needed.)
Earth’s Movement – Sundials
Materials:
Paper plate
Unsharpened pencil
Modeling clay or putty
Compass
Marking pen
Poke a hole in the middle of the paper plate, large enough for the pencil to fit through. You might need an adult’s help with this.
Stick the pencil through the plate. Make sure the bottom of the plate is facing up.
Anchor the end of the pencil in the putty below the plate to anchor the pencil in place.
Use the compass to locate true north and place your sundial in an open space with the pencil pointing slightly to the north.
Pick any hour of daylight, as long as there is sunlight to begin. If it is 6:00 a.m., put a mark where the shadow is on the paper, and label it 6:00. Continue this step every hour (or two hours) throughout the day and you’ll have a working sun dial!
Science Drops:
The Earth moves around the sun, and we spin on our axis. Each rotation on our axis equals one day; each revolution around the sun equals one year.
As the shadow moves around your paper plate sundial, it shows the Earth’s movement. Earth, where we are, is moving just under 1,000 miles per hour!
|
