Favorite Physics Demonstrations

Kevin Dwyer CSULB PhysTEC Teacher in Residence

Cypress High School, Anaheim Union HSD

Laura Henriques CSULB Science Education Department

CSTA President-Elect

Saturday, October 20, 2012

Welcome!

• Your handouts vs. what we’ll post online after our session

• Agenda – Force & Motion

– Circular Motion

– Energy & Momentum

– Electricity & Magnetism

– Thermodynamics

– Waves & Optics

– A few more of our favorite things!

Diving Eggs

• Relevant Topic/Unit: Inertia, Newton’s Laws

• Materials: beaker, water, pie plate, cardboard paper towel tube, raw egg, broom

• Set-up: Fill beaker ½ way with water. Place pie plate on top of beaker. Put cardboard tube directly over the beaker. Place egg horizontally on top of cardboard tube. You need the edge of the pie plate to extend beyond the edge of the table.

• Safety Considerations: keep area behind the pie plate clear

• Relevant Topic: Projectile Motion

• Materials: – Launcher($20: amazon.com)

– Sponge balls and buckets or water balloons

• Set-up: Teams of 3 or 4 students, large field

• Safety Considerations: Caution students not to aim/shoot at anyone close

Angry Nerds

Blue plate special….Circular Motion

• Relevant Topic/Unit: Circular Motion

• Materials: displosable clear plastic plate, marble, ruler with a ridge, overhead projector (additional plastic plates and marbles optional) (could be done with document camera)

• Set-up: Cut clear plate in half and put on overhead projector. You will be rolling a marble down a ruler onto the edge of the plate to see where it leaves the plate

• Safety Considerations: nothing special

• What happens to a marble that is rolling around the edge of a plate when it comes to the end?

• Relevant Topic: Circular Motion, Forces

• Materials:

– Flying Pigs $9: arborsci.com, teachersource.com, amazon.com

– (Optional: magnetic hooks & swivel)

• Set-up: Attach to ceiling using included hardware or with magnetic hook and swivel

• Safety Considerations: Caution students to be aware of flying pigs!

Flying Pigs!

• Relevant Topic: Electricity

• Materials: Chirping Chicks ($2: amazon.com)

• Set-up: Have a group of students hold hands in a circle. Join in the circle by taking one student’s hand. In your other hand hold the chick with one finger on one of the electrodes on the bottom. Ask the student next to you put one finger on the other electrode.

• Safety Considerations: None

Chirping Chick

Hotdog Circuits

• Relevant Topic/Unit: Electricity (series & parallel circuits)

• Materials: stripped extension cord (male end intact), skewers, block of wood, hotdogs, stopwatch (or clock with second hand) [OR wood with five nails with electric cord attached] buns and condiments optional!

• Set-up: you will create circuits where the hotdog is the resistor

• Safety Considerations: 120 volts with exposed conducting ends! I like to use a power strip to turn on/off the current. Hotdog will be very hot but the ends of the hotdog which are not part of the circuit will still be cool.

• Relevant Topic: Electricity & Magnetism • Materials: Eddy Current or Lenz’ Law Kit

(from $20 - $100 depending on size: any scientific retailer or even magic shops! You can also make your own.)

• Set-up: Drop the steel mass through the tube. Then drop the neodymium magnetic mass through the tube.

• Safety Considerations: None

Lenz’s Law

• Relevant Topic: Energy, Thermodynamics

• Materials: Smashing Spheres ($28: teachersource.com), paper

• Set-up: Have a student hold up a piece of paper. Quickly bring the spheres together from about 1 meter apart until they collide with the paper in between them.

• Safety Considerations: Be careful to make sure there are no fingers between the spheres when they collide.

Smashing Spheres

Crushing Can

• Relevant Topic/Unit: thermo • Materials: empty soda can, water,

heat source (hot plate, bunsen burner), tongs, large bowl/container

• Set-up: put ~1-2 ml water in soda can. Heat water in the can until it boils. With tongs or hot gloves, quickly take the can off the heat and invert it into a container of water (cold water is more dramatic). Be sure that the opening at the top of the can is fully submerged.

• Safety Considerations: The can will be hot. Take appropriate precautions.

• Relevant Topic: Waves • Materials:

– Skewer sticks – Gummi bears – Duct tape – Ring stands/clamps

• Set-up: Have students place a gummi bear on each end of a skewer. Place skewers 5 cm apart on duct tape. Fasten each end to ring stand.

• Safety Considerations: Warn students to exercise caution with the sharp ends of skewers

Gummi Bear Waves

Now you see it, now you don’t

• Relevant Topic/Unit: Optics (reflection)

• Materials: pair of matching candles, matches, pane of glass (picture frame works fine), clay or binder clips to hold glass perpendicular to the table

• Set-up: 1. Secure the glass perpendicular to the table. 2. Place one candle on the table in the upright position on one side of the glass. 3. Place the other candle upright on the table on the other side of the glass along the same line and the same distance as the first candle.

• Safety Considerations: open flame

• Relevant Topic: Optics • Materials:

– Mirage Mirror ($12: amazon.com, or $35: arborsci.com & teachersource.com-better quality image)

• Set-up: Place a small object, such as an M&M or a gummi bear in the bottom of the mirror . Place the mirror by the entrance to your room and watch the reactions as they enter your room and look at it.

• Safety Considerations: None

Mirage Mirror

Magic Penny

• Relevant Topic/Unit: Optics (refraction)

• Materials: opaque bowl, penny, water

• Set-up: Give groups a bowl, penny and beaker of water

• Safety Considerations: N/A

PHET Simulations which align with today’s demos

• Projectile Motion (Angry Nerds) http://phet.colorado.edu/en/simulation/projectile-motion

• Waves (Gummi Bear Waves) http://phet.colorado.edu/en/simulation/wave-on-a-string

• Refraction (Magic Penny) http://phet.colorado.edu/en/simulation/bending-light

• Electricity (Hotdog Circuits) http://phet.colorado.edu/en/simulation/circuit-construction-kit-dc http://phet.colorado.edu/en/simulation/circuit-construction-kit-dc-virtual-lab

Photo Project (based on the AAPT Photo Contest & activity from Katie Beck)

• Relevant Topic/Unit: any topic works

• Materials: digital camera and the world!

• Set-up: assign students to take pictures which illustrate physics concepts. In addition to the picture students must submit a written description of the physics

• Safety Considerations: none

THANK YOU! • If you are in the Long Beach area, please join us on the 2nd Thursday of the

month for Physics Demo Days. Details and RSVP information available online at www.physicsatthebeach.com. Contact us about viewing demo day online (we are experimenting with streamed video options).

• Next week (10/27) will be the CSULB PhysTEC Open House. Secondary physics teachers and a few of their students are invited to join us for a morning of physics. Details and RSVP information available online at www.physicsatthebeach.com.

http://www.classroomscience.org/what-makes-for-an-effective-science-demonstration

Enjoy the rest of the conference!

• Kevin Dwyer <chsdwyer@yahoo.com> • Laura Henriques <laura.henriques@csulb.edu>