Physical Science Sampler

Physical Science Sampler

Grade level: Middle school
Program description: Motion, electricity, magnetism, sound, light and heat are branches of classical physics explored with special emphasis on how they relate to one another. The motion experiments illustrate concepts of forces, friction and types of energy. Electricity
and magnetism are related through the use of a Magneto Generator.

  • Students gain first hand experience with conductors, insulators, open and closed circuits, as well as series and parallel circuits.
  • Static and current electricity are examined with the Van de Graff Generator and Tesla coils.
  • Properties of waves, their amplitude, frequency and wavelength are experienced through the use of an oscilloscope.
  • Prisms and strobe lights illustrate principles of reflection, refraction and absorption of different types of waves.

Note: Curriculum alignments based on requirements for Hamilton County, Tennessee including 6.14.spi.1, 6.14.spi.2, 6.14.spi.4, 8.10.spi.3

Pre-visit activity – Explore the Doppler Effect

Materials:
Two people
Digital watch with an alarm
7 feet of string

What to do
1. Move to an open space with at least 15’ of clear space. Outside is best.
2. Securely tie the watchband of the watch to the string. Set off the alarm on the watch.
3. Have person #1 hold onto the end of the string without the watch. Person #2 takes the end of the string with the watch attached and walks away from the other person until the string is taut. Person #2
sets the watch on the ground and then takes a couple more steps away so as to not get whacked by the whirling watch.
4. Person #1 pulls the watch back and begins to whirl the string and watch overhead gradually letting
out the string until it is at it full length. Don’t let go of the string!
5. What did person #1 hear? What did person #2 hear? Switch places and try again.

Outcome: For the person swinging the watch, the sound stays the same distance from the ears all the time, so the sound waves reach the ears at the same time and the pitch remains constant. For the person standing at a distance from the watch, the watch is moving closer or farther away during each rotation.

As the watch moves closer, the sound waves bunch up or get closer together increasing the frequency resulting in a higher pitch. As the watch swings away, the reverse is true. The waves are farther apart
resulting in a lower frequency and a lower pitch.

Post-visit activity – Explore color change in the sky

Materials:
Clean glass jar
Flashlight
Milk
Water
Teaspoon

What to do:
1. Fill the glass jar with cold water. Stir in one teaspoon of milk. In a darkened room, hold the flashlight to the side of the jar and shine it through the jar. The water looks blue.
2. Move the flashlight to the back of the jar so that it is shining through the jar toward the onlookers.
The light from the flashlight should look yellow, just like the sun.
3. Stir two more teaspoons of milk into the water. Shine the flashlight through the side and the water looks blue. Shine it from the back toward the onlookers and it looks pink.

Outcome: The milk in the water stops the short, weaker wavelengths of light from passing through the water. Only the red light waves get through making the water appear pink. A similar phenomenon occurs
at sunrise and sunset. When the sun is low in the sky, the water, dust and pollution in the air cause the sky to look pink.