The word Fossil comes from the Latin fossils meaning ‘dug up’. They are defined as the remains or traces of plants or animals that lived a long time ago. Fossils are usually preserved in sedimentary rocks such as sandstones, shale or limestone.
How are fossils formed? What common types of plants and animals are found as fossils?
Plastic bags are made of long chains of polymers (picture a bowl of cooked spaghetti before you add sauce). When you poke the pencil in the bag you are moving those strands a part. The elasticity of the bag pushes the strands back along the sides of the pencil, sealing the bag and keeping the water inside. When the pencil is removed, the strands will not completely return to their original position and the water will flow out of the holes.
Ask the students to predict what will happen before you stick the pencil into the bag. What if you used different brands or sizes of zipper type bags? Different types of pencils? Different volumes of water?
2 strips of paper (cut one strip 1 inch wide and 5 inches long, cut the second strip 1 inch wide and 10 inches long), ruler, scissor, pencil, non-bendable, plastic drinking straw, tape
Curl the paper strip into a hoop, taping the ends together. Tape the small hoop to one end of the straw, and the big hoop to the other end, making sure they are lined up together. Hold your Hoop Glider in the middle of the straw, with the small hoop in front and throw it gently like a paper airplane.
If you throw a plain straw, it doesn’t go very far. But when you add paper hoops, the straw glides through the air. That’s because the hoops act like wings. Things that fly—like insects, birds, and airplanes—all have wings.
Try changing the size of the hoops on your glider. How does it fly with different sized hoops? Why?
Each of the glasses will have a different tone when tapped with the pencil. The glass with the most water will have the lowest tone while the glass with the least amount of water will have the highest. Small vibrations are made when you hit the glass and this creates sound waves, which travel through the water. More water means slower vibrations and a deeper tone.
Does the temperature of the water make a difference in the sound? What happens if you use a spoon instead of a stick or pencil? REMEMBER to tap gently!
The Science
If you look at the top of the glass of water (which was the bottom), you’ll notice a small area of air. Because the rest of the glass is full of water, there’s no chance for more air to get into that area. This air represents an area of low pressure. There are more air molecules pushing up against the bottom of the note card, creating a higher pressure area, compared with the lower pressure area inside the top of the glass. The force from the atmospheric pressure outside holds the card up and the low pressure area in the glass, prevents the water from pushing the card down.
Water’s adhesion property also plays a role in this experiment. Adhesion occurs because water molecules are attracted to or stick to other materials. In this experiment, the water molecules are attracted to the paper, adhering to it, keeping the note card in place.
What if the glass is half full of water? What about one-fourth full? Does it work if you use a carbonated beverage instead of water?