Film Canister Capacitors

6769_100121036671012_100000193470961_521_4265928_nby: Norm Barstow

This is a guide on how to make a Leyden Jar that makes awesome sparks with materials you may even find in your house. It’s inexpensive, basically harmless and fun.

Here is the list of materials you will need:

  • An empty film canister with lid.  These are available at Educational Innovations.
  • Multistrand insulated wire; eg. type HPN Heater Cord
  • Single conductor/solid un-insulated wire, about 1.5 mm in diameter (16 gauge copper wire).
  • Some aluminum or copper foil. (NOTE: Any conductive foil will work. Copper foil is thicker and easier to work with than aluminum foil, but aluminum foil works. Heavy duty aluminum foil works best.
  • A bolt (10/24) with a round head that is shorter than the film canister’s height. Two nuts that fit the screw.  Washer is optional.
  • Scotch tape.

Film canister Capacitors

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Building a Hovercraft Science Project

6769_100121036671012_100000193470961_521_4265928_nLook, Mom, No Wheels!  | Building a Hovercraft Science Project

by:  Norm Barstow

The first practical design of the hovercraft was completed in the late 1950’s by British engineer, Sir Christopher Cockerell.  Since then, the continued development of this invention has been ongoing, and currently, the hovercraft is being used commercially, by the military, and for personal use.  Teachers have been constructing versions of the hovercraft using balloons, film canisters and flat materials in classrooms for years.

The principle behind the hovercraft’s levitation is that when the air is released from the balloon, it hits the ground and rushes outward in all directions. The air flowing from the balloon through the holes forms a layer of air between the hovercraft and the table. This reduces the friction (the resistance that occurs when two object rub against each other) that would have existed if the hovercraft rested directly on the table. With less friction, your hovercraft scoots across the table.

Furthermore, extra air molecules are packed underneath the structure, which in turn increases the pressure under the hovercraft.  This increased pressure below the craft produces an overall upward pressure force on the craft therefore it supports its weight. Since air molecules are always leaking out from beneath the craft, you’ll need a source of air molecules to replace them, which is provided by the balloon.

Materials:Building a Hovercraft Science Project

·      Large plastic plate (not the inflexible type)
·      Foam meat tray from grocery store  (6.5” X 8.5”)
·      Old CD
·      Stiff cardboard

  • Poster putty such as Blue Tak, or Poster Tak
  • Smooth surface
  • Hole instrument: Ball point pen tip or hot nail or drill.

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How to Make a Rocket (Scientist)

Tami O'Connorby:  Tami O’Connor

A few months ago I had occasion to conduct two hands-on workshops for elementary and middle school teachers at the NSTA National Convention in San Francisco on behalf of Educational Innovations.  One presentation focused on film canister rockets.  This is a tried-and-true way to teach Newtown’s First and Third Laws of Motion and also brings to light concepts such as the four forces of flight; thrust, drag, weight, and lift.  It also reinforces instruction on 3-D shapes and 2-D plane figures such as circles, cones, cylinders, rectangles, and triangles.

Make a RocketI presented the lesson to the teachers in much the same way I would to my students.  The first thing we did was to brainstorm the features all rockets have.  After a bit of discussion it was agreed that they all have a nose cone, a cylindrical body, fins, and an engine.  I then handed out a paper template imprinted with the pattern of a nose cone and fins, a regular 8½ x 11 sheet of white paper, a piece of goldenrod paper, and a white translucent film canister.  Also required are scissors, tape, ¼ piece of an Alka Seltzer tablet, and paper towels.

The only canister that works with this rocket is the type that has the lid that fits snugly inside the canister.  The canisters that have a lid that wraps around the outside rim, however, will not allow enough pressure to build up inside the chamber.

How to Make a Rocket

The first step in building a film canister rocket is to construct the body of the rocket.  The easiest way is to curl the white 8 ½ x 11 paper into a cylindrical shape using the film canister (without the top) as a guide.  The paper can be rolled around the film canister and then taped along the edges.  The easiest way to recover the film canister is to blow into one end of the rolled cylinder, forcing the canister out the other end. Read the rest of this entry »