Untitled Document

Physics Demo Number: 161

Approximate

Run Time: 8 min

Electrostatic Field Apparatus for Overhead with Spark Gun

Demo Description

A tray contains tiny dipole elements in solution that can line up along the electric field lines of charged metallic overlay electrodes.

Scientific Principles

Dipoles line up with external electric field lines.

Equipment

Electrostatic Field Apparatus For Overhead Projector Proprietary Apparatus by Nakamuro.

Equipment Location

Kit (161) on [B-1-6]

Instructions

The base tray, with parallel plate capacitor overlay electrode assembly in place , is seen in the first photo.

The spark gun and four more electrode configurations are seen in the second photo.

The last photo shows the other four electrode sets a little better , along with their storage container.

Notes: One must be CERTAIN to lay the electrode metal against the top surface of the base tray. (Put it on upside down and it won't work!)

One should leave the base tray on the activated overhead for only SHORT times, several minutes maximum, to avoid HEAT damage to the base tray.

Be sure the plastic retaining bar for the base tray is in place when picking the whole unit up to clear the field records and remove air bubbles.

Touch the nose of the gun to its ground electrode before touching it to the red electrode of the base tray.

Squeeze the trigger slowly and smoothly, being sure not to let off of the squeeze any at all, before disengaging the nose of the gun from the red electrode.

Kit for apparatus is on [B-1-6].

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Direct evidence of the electric field of a charged rod ( with pith balls as detectors) can be set up as seen in the next two photos.