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Demo Code: EM-B-ED
Pira Index: 5B 30.30



  1. Pasco Van de Graaff
  2. Point & sphere asembly w/string
  3. 1/2″ PVC pipe for vertical support
  4. Telescope clamp & wood block

  1. By hand cranking the Van de Graaff, charge the sphere and point assembly.
  2. When you stop charging, the charge quickly begins to drain off through the string attached to the Van de Graaff.  Note which, the point strings or the sphere strings, retain charge by watching the collapsing of the strings attached to each.  (The sphere with its large radius loses charge more rapidly than the point.)

Dirod Machine

Demo Code: EM-A-DR
Pira Index: 5A 50.20


  1. Dirod Statics generator
  2. Dissectible Leyden jar
  3. 2 AA leads
  4. Discharging tongs

  1. Connect the Leyden jar to the Dirod generator as shown.
  2. Crank the Dirod clockwise to charge the capacitors
  3. Use the discharging tongs to show there has been a build up of charge.

Atmospheric Pressure Can

Demo Code: FM-B-AC
Pira Index: 2A 30.25

Demonstrates the force of atmospheric pressure.


  1. Air/Vacuum pump
  2. Metal Can
  3. Stopper with copper tube (stored with can if it is saved)

  1. Connect vacuum hose to can.
  2. Evacuate can.
  3. Observe effects.
  4. Replace vacuum hose with air hose.
  5. Pump the can back to it’s original shape.

Notes: In using this demo the can is crushed & restored. The can may be too bent up to be used a second time. Extra cans are stored in 241 A –A–0

Caution: When pumping air into can do not over pressurize. Hose can pop off.

Cohesion Plates

Demo Code: FM-A-CP
Pira Index: 2A 10.35

Molecular cohesion holds two metal disks together.


  1. Cohesion disks

  1. Place the disks tightly together and let them hang from one handle being careful not to let them slide apart or fall & get damaged.

Notes: Careful not to damage the surface of these plates. They must be kept smooth & clean. Make sure these plates are thoroughly dried before putting away.

Capillary Action

Demo Code: FM-A-CA
Pira Index: 2A 20.10

Demonstrates the principles of pressure and energy.


  1. Capillary set with support
  2. Colored Water

  1. Fill lower tray with water.
  2. Note that the fluid rises higher in the small tubes than the large ones.


Air Pressure Balloons

Demo Code: FM-A-AP
Pira Index: 2A 10.52

Demonstrates the principles of pressure and energy.


  1. Stopcock
  2. Two identical balloons
  3. Rubber bands

  1. Blow air into two balloons, leaving one balloon noticeably smaller.
  2. Attach balloons to stopcock using rubber bands to prevent leaking.
  3. Turn stopcock to open position.
  4. Observe that the smaller balloon blows up the larger balloon.  Why?


Demo Electroscope

Demo Code: EM-A-DE
Pira Index: 5A 10.10

Demonstration showing the presence of static charge.

video link: electroscope

Lab Equipment


1.  Demo electroscope2.  Large PVC rod

3.  Large plastic rod

4.  Paper towel

1.  Rub one of the rod using the paper towel to give it a  charge.  PVC  takes on a negative charge and the plastic tube becomes positively charged.2.  The electroscope works best if charged by induction.  Hold the charged rod close (but not touching) to the electroscope.  Touch the sphere with your hand, remove your hand and then remove the rod.  The scope is charged oppositely to the rod’s charge.

Bipolar Rods

Demo Code: EM-A-BR
Pira Index: 5A 20.10


Lab Equipment Direction
1.  Special rods (all are not shown)largeacrylic-PVC combinationPVC rodacrylic rod

thin acrylic-PVC combination

thin PVC rod

thin acrylic rod

metal rod

wooden rod

2.  Low friction pivot

3.  Paper towel

1.  Using the paper towel, charge both ends of acombination acrylic-PVC rod and place it on the swivel (the thin set works well on the overhead).

2.  Again with the paper towel charge the acrylic rod. Bring it near the acrylic end of the mounted rod– it repels.  Bring it near the PVC end & it attracts.

3.  Repeat with the PVC rod and any of the other rods youwish to try.