NOTE: YOU MUST CHOOSE TWO ACTIVITIES! You must use graph paper and you must follow your lab write up procedures.
1. Density Demonstration: Pour water into one glass until it is half full. Put an egg into the water. Notice what happens. Now add 3 tablespoons of salt, stir gently and observe what happens. Pour water into a second glass until it is half full. Stir in 10 tablespoons of salt. Slowly add fresh water until the glass is full. Do not stir. Gently lower the egg. What happens? Use your knowledge of density and buoyancy to explain
2. What Gives? : Show your family how liquids and gases differ. Completely fill the bulb and cylinder of a turkey baster with water (or secure a pipet from your teacher). Hold it over the sink. While you seal the end with your finger, have a family member squeeze the bulb. Now let the water out of the turkey baster. Again, seal the end with your finger and have a family member squeeze the bulb. Was there a difference? Use what you know about liquids and gases to explain the observations.
3. News Data: Look for graphs in your newspaper or in magazines. Point out to members of your family which variable is the manipulated variable and which is the dependent variable for each graph. Determine whether the line graphs are showing that the two variables are directly proportional or inversely proportional. Place these graphs in your lab notebook with your explanation.
4. Fingernail Growth: Have each member of your family measure the length of the white part at the end of one fingernail. Write down the results (and which finger you used) and mark your calendar for a date in exactly three weeks. On that day, measure the new length of the white part of the same fingernail. Then calculate the speed, in millimeters per day at which your fingernail grew. Compare your results.
5. Coin Inertia: Fill a paper cup with water. Cover the cup with an index card and place a coin or paper clip in the center of the index card. Challenge your family members to move the coin from the card to the cup without touching the coin or holding on to the card. If they cannot think how to do it, show them how. Hold the cup and use your finger to flick the card with a sharp sideways force. The force doesn’t have to be very strong, but it must be sharp. Explain what happens to the coin in terms of inertia.
6. Swing the Bucket: Fill a small plastic bucket halfway with water and take outdoors. Challenge a family member to swing the bucket in a vertical circle. Explain that the water won’t fall out at the top if the bucket is moving fast enough. Tell your family members that if the bucket falls as fast as the water, the water will stay in the bucket. Relate this activity to a satellite that also falls due to gravity, yet remains in orbit.
7. Under Pressure: Fill a small plastic container-a bottle or a cup-to the brim with water. Place an index card over the entire opening of the container. Ask your family to predict what would happen if the container were turned upside down. Over a sink, test the predictions by slowly turning the container upside down while holding the cardboard in place. Let go of the cardboard and see what happens. Without touching the cardboard, turn the container on its side. Use air pressure to explain why the cardboard stays in place and why the water stays in the container.
8. Atomizer: You can make your own atomizer using a straw. Cut a plastic straw partway through. Hold one end of the straw in a glass of water and bend the other half of the straw at a right angle at the cut. Blow hard through the straw, making sure that no one is in the way! Show your device to your family. See if they know what it is and why it works. Explain the device to them in terms of Bernoulli’s principle.
9. Household Machines: Have a family member examine hand-powered devices around your home. You might pick a hand tool like a shovel, hammer, or screwdriver or a kitchen utensil such as a knife or egg beater. Explain the idea of input and output forces. Then have him or her identify the input and output forces for the device you picked.
10. Finger Forces: Have a family member place a wooden toothpick between the ends of his or her fingers near the tips. Ask that person to try to break the toothpick by pressing down with the first and third fingers. Now repeat the procedure, but this time have the person hold the toothpick much nearer the hand. Explain to your family why the toothpick was easier to break on the second try. How were the positions of the forces and fulcrum different in each case?
11. Tough Newspaper: Place a wooden ruler or similar strip of wood on a table so that 2 inches projects over the edge. Spread a double sheet of newspaper over the ruler so the paper lies flat along the table edge. Strike the projecting edge of the ruler hard. What happens? Explain the results in terms of force and air pressure.