How to Make Cool Experiments
Hands-on experiments engage students' attention while teaching basic chemistry and physics. Accessible topics include force, motion and waves. An unbalanced force produces a change in motion or acceleration, while a balanced force creates tension. Some materials under tension will change shape through extension, twisting, compression and bending. More force is necessary with increased resistance. Waves have common properties in water, air or ground. Waves deliver energy. Waves travel at the same speed in all directions. Waves can be reflected. Interference occurs when two waves meet, and they can strengthen or cancel each other.
Things You'll Need
- String
- 2 elastic bands
- Steel spring
- Latex foam block
- Safety goggles
- 2 pencils
- 3 meter flexible rope
- Flexible metal spring
- Ripple tank or tub
- Water
- Water dropper
- Wooden ruler
- Small wooden board
Instructions
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Experiments
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1
Hold one end of the string and pull. Hold both ends of the string, pull simultaneously, and note the difference. Repeat with an elastic and steel spring. Hold the latex foam block in two hands. Pull both ends. Twist the ends in opposite directions. Compress the ends. Bend the block.
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2
Hang two elastics from a pencil. Insert a second pencil through each loop and pull down. Connect two elastics by looping one through the other. Insert a pencil and pull down.
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3
One person holds the end of a long flexible rope, keeping it still in midair. The second person stands 3 meters away and quickly jerks the rope up and down. Repeat using different speeds and ranges of motion. Repeat step 3 using a flexible metal spring held on the floor.
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4
Pour water into ripple tank or tub until half full. Touch water once in the middle of the tank. Touch water four times in succession. Squeeze one drop of water into the tank. Squeeze four drops in rapid succession.
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5
Place the ruler on the water surface at one end of the ripple tank or tub. Tap the ruler once. Tap several times at varying intervals. Note the wave shape at each end of the tank.
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6
Position a wooden board in the water, oriented straight across the tank near one end. Place a ruler on the water at the opposite end and tap once. Repeat with the board at different angles smaller and larger than 45 degrees.
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7
Place a wooden board in the center of a water tank. Squeeze one drop of water into the water and let ripples hit the board. With one hand, locate where the wave appears to reflect back. With two fingers, start two simultaneous waves from the original point and reflection point.
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1
Tips & Warnings
Expand on these experiments to explore related concepts. Use different barrier shapes, such as parabolic and elliptical, in the wave experiment.
Use safety procedures at all times, particularly with elastic materials in force experiments.
