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NOTE:  CHOOSE TWO LABS.  You must use graph paper and you must follow your lab write-up procedures!

1.  Waves in a Sink: With your parent’s permission, fill the kitchen sink with water to a depth of about 10 cm.  Dip your finger in the water repeatedly to make waves.  Demonstrate reflection and interference to your family members.  Try to think of ways to demonstrate refraction and diffraction as well.

2.  Sounds Solid:  Find out how disturbances travel through different solids.  Have a family member or friend tap one end of the table with a spoon.  Now put your ear down on the other side of the table and listen to the tapping again.  What difference do you notice?  Repeat the tapping on various surfaces around your home.  What observations have you made?

3.  Ear to the Sound:  Find a long metal railing or water pipe.  CAUTION:  Beware of sharp edges and rust.  Put one ear to the pipe while a family member taps on the pipe some distance away.  Do you hear the sound first with the ear touching the pipe or with your other ear?  Compare the sound you hear through the metal with the sound coming through the air.  What accounts for the difference?

4.  Sunglasses:  On the next sunny day, have family members go outside wearing their sunglasses.  Which sunglasses have polarizing lenses?  How can you tell?  Through the sunglasses, look at surfaces that create glare, such as water or glass.  Compare the effects of different pairs of sunglasses.  Which kind of sunglasses are best designed to reduce glare on a sunny day?  CAUTION:  Do not look directly at the sun.

5.  Pencil Bending:  Here’s how you can bend a pencil without touching it.  Put a pencil in a glass of water.  Have your family members look at the pencil from the side.  Using the idea of refraction, explain to your family why the pencil appears as it does.

6.  Optical Illusion:  Roll a sheet of paper into a tube and hold one end up to your right eye.  Hold your left hand against the left side of the far end of the tube with your palm facing toward you.  Keeping both eyes open, look at a distant object.  Draw and label a diagram of what you see.  What do you think causes this optical illusion?

7.  House Magnets:  Explore your home with a compass.  Use the compass to discover objects that are magnetized.  For example, test the top and bottom of the stove, refrigerator, or a metal filing cabinet. Try metal objects that have been in the same position over a long period of time.  Explain why these objects attract or repel a compass needle.

8.  Standing on End:  Rub a balloon against your hair and bring the balloon near one of your arms. Then bring your other arm near the front of a television screen that is turned on.  Ask a family member to explain why the hairs on your arms are attracted to the balloon and the screen.  Explain that this is evidence that there is a static charge on both the balloon and the screen.

9.  Recharge Your Batteries:  Can you revive a dead battery?  Try the following with two old D cells and a flashlight.  Test the flashlight with the old D cells and observe its brightness.  Then ask a family member to remove the D cells and place them in direct sunlight to warm them up.  After an hour or more, use the cells to test the flashlight.  How does the brightness of the bulb compare in the two tests?  Explain to your family how a cell works.  Then discuss what your observations indicate about the chemical reactions in the battery.

10.  Remote Controls:  A remote-control device uses electromagnetic waves to program an electronic device- for instance, a television, VCR, radio or toy- from a distance.  Find a device with a remote control.  Ask your family members to help you locate the receiver for the remote control on the device.  Find out how far away from the device you can stand and still control the device.  Find out what objects the waves will travel through.  Will they bounce off mirrors?  Off walls?  Off you hand?

11.  Computer Age:  Although computers are commonplace today, this was not always the case.  Interview a family member who grew up before computers were common.  Prepare a list of questions for the interview.  Find out whether that person has used a computer, what he or she thinks about computers, and how computers might have changed his or her life.  Ask if the large number of applications for computers has come as a surprise.