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Liquid Amazement
Let’s find out what happens when you shine your laser through liquids.
Procedure:
1. With the permission of a responsible adult, fill up three clear glasses with tap water.
2. Leave one alone. Add about 1 tablespoon of salt to the second. Add about 1 tablespoon of
sugar to the third. Mix the sugar in well with a spoon. Place ice cubes in the fourth glass.
Fill a fifth glass with olive or vegetable oil (use a small glass if you can, to save the oil).
3. Carefully take the glasses into a dark room and set them down.
4. Shine your laser beam into each of the glasses. Try from the side. Then try from the top.
5. Line up the glasses and try to shine your beam through each from the side.
6. Enjoy the show!
Results:
Light travels differently through different liquids. It scatters off particles suspended in those liquids. You should be able to see
the whole beam when you shine your light from the side through the oil and salt water. Different-sized oil molecules scatter the
light to reveal a tight beam. Undissolved particles in the salt water also scatter the light, producing a cloudy beam. You won’t
see a complete beam through the clear water or sugar water. There are fewer suspended particles to bounce back the light. But,
do you see any in the sugar water? How does the sugar water look different than the salt water? And what happens when you
shine your laser through the glasses from the top? What happens if you let the salty and sugary glasses sit for an hour and then
shine your light through?
Materials:
• Laser
• 3-5 Clear glasses
• 3 Cups of water
• 1 Tablespoon salt
• 1 Tablespoon sugar
• Olive or vegetable oil
• Tablespoon
• 1 Cup of ice cubes
• Measuring cup
More Laser Fun:
With the permission of a responsible adult, boil water and carefully pour it into a clear mug or clear measuring cup. Shine
your light through from the side and from the top. Compare with water at room temperature. Or, compare what you see when
you shine your laser through tap water with distilled water or mineral water. Or, try to mix and match water and oil in one glass.
Explore! Remember, these experiments work best in a dark room.
oil
sugar
water
salt
water
tap
water
ice
cubes