Experiment # 7
Need:
magnet, bowl, paper bowl, water, tape, marker
Method:
1. Put the plastic dish in front of you. Tape the magnet to the middle of the dish with the N and the S showing and with N pointing away from you. With a permanent marker write over the N and the S of the magnet to make it easier to see, and write a W and an E on the dish.
2. Next fill a cereal bowl ¾ full of water. Then place the plastic dish gently in the cereal bowl. Make sure it stays afloat by not getting water in it. Also, the plastic dish should not be touching the sides of the bowl (to keep it floating freely).
Results:
No matter how you turn the bowl, the N should always point in the same direction.
Conclusion:
The north poles of all the magnets point to the Earth’s magnetic north pole in the same direction.
So no matter where you are, the N of the magnet of the compass will always point North.
Experiment #8
Need:
magnet, 2 pins, plastic bottle caps, bowl, modeling clay
Method:
1. Magnetize 2 pins by stroking it with the bar magnet from the head to the point 30 times (one direction only).
2. Stick the pins onto the top of the bottle caps using modeling clay.
3. Put the “boats” into a bowl of water.
4. See what happens.
Results:
The “boats” will float towards each other, with the head of one pin facing the point of the other pin.
Conclusion:
The ends of the pins have different poles so they are attracted to each other (the head of one is attracted to the point of the other.)
Static Electricity
Kit 26 Experiment #1, #2 we have already done.
1 blowing up 2 balloons, tying a string to each letting them fall together
Then rubbing them and observing them repel from each other
2 rub a balloon on your hair and observe your hair standing on end.
Experiment # 3
Need:
Balloon, clean hair
Method:
1. Rub a balloon on your hair and try to stick it to various objects.
Recharge the balloon by rubbing on your hair at least 5 seconds each time before trying to stick it onto a new object.
Need:
magnet, bowl, paper bowl, water, tape, marker
Method:
1. Put the plastic dish in front of you. Tape the magnet to the middle of the dish with the N and the S showing and with N pointing away from you. With a permanent marker write over the N and the S of the magnet to make it easier to see, and write a W and an E on the dish.
2. Next fill a cereal bowl ¾ full of water. Then place the plastic dish gently in the cereal bowl. Make sure it stays afloat by not getting water in it. Also, the plastic dish should not be touching the sides of the bowl (to keep it floating freely).
Results:
No matter how you turn the bowl, the N should always point in the same direction.
Conclusion:
The north poles of all the magnets point to the Earth’s magnetic north pole in the same direction.
So no matter where you are, the N of the magnet of the compass will always point North.
Experiment #8
Need:
magnet, 2 pins, plastic bottle caps, bowl, modeling clay
Method:
1. Magnetize 2 pins by stroking it with the bar magnet from the head to the point 30 times (one direction only).
2. Stick the pins onto the top of the bottle caps using modeling clay.
3. Put the “boats” into a bowl of water.
4. See what happens.
Results:
The “boats” will float towards each other, with the head of one pin facing the point of the other pin.
Conclusion:
The ends of the pins have different poles so they are attracted to each other (the head of one is attracted to the point of the other.)
Static Electricity
Kit 26 Experiment #1, #2 we have already done.
1 blowing up 2 balloons, tying a string to each letting them fall together
Then rubbing them and observing them repel from each other
2 rub a balloon on your hair and observe your hair standing on end.
Experiment # 3
Need:
Balloon, clean hair
Method:
1. Rub a balloon on your hair and try to stick it to various objects.
Recharge the balloon by rubbing on your hair at least 5 seconds each time before trying to stick it onto a new object.
Results:
OBJECT | MATERIAL | STICKS (yes or no) |
Wall | Wood | Yes |
Refrigerator | Metal | Yes |
Table | Wood | Yes |
Clothes | Cotton, wool | Sort of |
Doorknob | Metal | No |
Balloons stick better to some materials than others
Experiment #4
Need:
Balloon, clean hair, anti-static sheet (dryer sheet)
Method:
1. Rub a balloon on your hair 10 times and stick it to a wall.
2. Take the balloon off the wall.
3. Take the anti-static sheet and rub it all over the balloon.
4. Now try to stick the balloon on the wall again.
Results:
The balloon no longer sticks to the wall.
Conclusion:
The anti-static sheet puts a layer of conditioning soap on the balloon.
This soap attracts moisture out of the air, which conducts electricity and causes the static charge to disappear.
This is how dryer sheets work on clothes and similarly how hair conditioners work.
Experiment #5
Need:
Balloon, clean hair, stop watch or other second hand timer
Method:
1. Rub a balloon on your hair 10 times and stick it to a wall. Time how long it sticks.
2. Rub a balloon on your hair 10 times and stick it to a wall in a bathroom after the shower has been running on hot for a while so the bathroom is humid. Time how long it sticks.
Results:
The balloon in the shower sticks for a shorter time.
Conclusion:
The hot water from the shower creates humidity, which are tiny droplets of water floating in the air. Water is the air allows electrons to move away from the balloons. As the electrons move from the balloon to the water in the air, the static charge on the balloon is decreased and it falls off the wall faster than it does in non-humid air. Since it tends to be more humid in summer, there is less static electricity in the summer than in the winter (when the air is dry.)
Experiment #6
Need:
Clean hair, comb
Method:
1. Move a comb through your hair until your hair starts to stand straight up. This works best with longer hair.
Results:
The hair stands straight up.
Conclusion:
When the comb is moved through the hair, the comb and hair become oppositely charged. However, since each strand of hair has the same charge and like charges repel, the strands of hair repel one another and stand straight up.
Experiment #7
Need:
Clean hair, comb
Method:
1. Move a comb through your hair until your hair starts to stand straight up. This works best with longer hair.
Results:
The hair stands straight up.
Conclusion:
When the comb is moved through the hair, the comb and hair become oppositely charged. However, since each strand of hair has the same charge and like charges repel, the strands of hair repel one another and stand straight up.
Experiment #8
Need:
Clean hair, Styrofoam handle, pie tin, Styrofoam plate
Method:
1. Tape the Styrofoam handle to the bottom of the pie tin.
2. Rub the bottom of the Styrofoam plate on your hair. Do it fast and all over your head.
3. Put the plate upside down on the table (with the bottom facing up)
4. Pick up the pie tin by the handle and hold it about 3 inches above the Styrofoam plate and drop it onto the Styrofoam plate (make sure it does not fall off the plate)
5. Very slowly touch the pie tin with the tip of your finger. Make sure you do not touch the Styrofoam plate. Look for a spark.
6. Try this in the dark
Results:
When the finger touches the pie tin, a spark is formed.
Conclusion:
The Styrofoam plate pulls electrons off your hair when it is rubbed. When the aluminum pie tin is put onto the Styrofoam plate the pie tin’s free electrons (electrons in a metal that can move around) try to get away from the electrons on the Styrofoam plate. When the finger touches the pie tin, they “jump” to your hand, creating a spark.
Experiment #9
Need:
Clean hair, plastic, nylon, latex (the balloon) and felt
Method:
Test the following materials to see which ones are good at creating static electricity;
Plastic, nylon, latex (the balloon) and felt by doing the following:
1. Take the material to be tested and rub it on your hair.
2. Put the material on the table. Grab the pie tin by the handle and place it on the material.
3. Slowly move your finger toward the tin until you either hear a spark or touch the tin.
4. Repeat this for the other materials. If a spark is created, you still need to touch the tin with your finger before dropping it again to “neutralize” its charge.
NOTE: The balloon creates so much static electricity that sparks can sometimes be heard when the pie tin is put onto the balloon.
Results:
Conclusion:
Latex and nylon are materials that are good at producing a static electric charge. Plastic and felt are materials that are not good at producing a static charge.
Experiment #10
Need:
Clean hair, balloon, cereal,
Method:
1. Put the cereal on a table.
2. Rub a balloon on your hair.
3. Hold the balloon just above the cereal but not touching the cereal.
4. Observe.
Results:
The cereal jumps up to the balloon, sticks to it and then drops back to the table.
Conclusion:
When you rub the balloon, the balloon becomes positively charged as the negatively charged electrons jump into the air. Cereal is neutral (it has an equal number of positive and negative charges) but when it is exposed to the positive charge of the balloon, the negative charges of the cereal are attracted to the balloon and they jump up and attach to it. When the cereal touches the balloon, the charge difference is lost and the cereal drops back down.
Technology
On the pages of Marvels and Mysteries of Science Brennan read about Body Mechanics, cyborgs, what scientists have done using the brain of an eel, robots that help scientists learn how they can help those who have had strokes, and experiments scientists are doing with a monkey’s brain.
Experiment #8
Need:
Clean hair, Styrofoam handle, pie tin, Styrofoam plate
Method:
1. Tape the Styrofoam handle to the bottom of the pie tin.
2. Rub the bottom of the Styrofoam plate on your hair. Do it fast and all over your head.
3. Put the plate upside down on the table (with the bottom facing up)
4. Pick up the pie tin by the handle and hold it about 3 inches above the Styrofoam plate and drop it onto the Styrofoam plate (make sure it does not fall off the plate)
5. Very slowly touch the pie tin with the tip of your finger. Make sure you do not touch the Styrofoam plate. Look for a spark.
6. Try this in the dark
Results:
When the finger touches the pie tin, a spark is formed.
Conclusion:
The Styrofoam plate pulls electrons off your hair when it is rubbed. When the aluminum pie tin is put onto the Styrofoam plate the pie tin’s free electrons (electrons in a metal that can move around) try to get away from the electrons on the Styrofoam plate. When the finger touches the pie tin, they “jump” to your hand, creating a spark.
Experiment #9
Need:
Clean hair, plastic, nylon, latex (the balloon) and felt
Method:
Test the following materials to see which ones are good at creating static electricity;
Plastic, nylon, latex (the balloon) and felt by doing the following:
1. Take the material to be tested and rub it on your hair.
2. Put the material on the table. Grab the pie tin by the handle and place it on the material.
3. Slowly move your finger toward the tin until you either hear a spark or touch the tin.
4. Repeat this for the other materials. If a spark is created, you still need to touch the tin with your finger before dropping it again to “neutralize” its charge.
NOTE: The balloon creates so much static electricity that sparks can sometimes be heard when the pie tin is put onto the balloon.
Results:
MATERIAL | SPARK (yes or no) |
Plastic | Yes |
Nylon | Yes |
Latex (balloon) | Yes |
Felt | Yes |
Conclusion:
Latex and nylon are materials that are good at producing a static electric charge. Plastic and felt are materials that are not good at producing a static charge.
Experiment #10
Need:
Clean hair, balloon, cereal,
Method:
1. Put the cereal on a table.
2. Rub a balloon on your hair.
3. Hold the balloon just above the cereal but not touching the cereal.
4. Observe.
Results:
The cereal jumps up to the balloon, sticks to it and then drops back to the table.
Conclusion:
When you rub the balloon, the balloon becomes positively charged as the negatively charged electrons jump into the air. Cereal is neutral (it has an equal number of positive and negative charges) but when it is exposed to the positive charge of the balloon, the negative charges of the cereal are attracted to the balloon and they jump up and attach to it. When the cereal touches the balloon, the charge difference is lost and the cereal drops back down.
Technology
On the pages of Marvels and Mysteries of Science Brennan read about Body Mechanics, cyborgs, what scientists have done using the brain of an eel, robots that help scientists learn how they can help those who have had strokes, and experiments scientists are doing with a monkey’s brain.
A trip to brain pop, watching a movie, taking a test and off to several stops on the internet to learn about electromagnets, and batteries.
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