Induced Charge Concept

Demonstrations in Induced Charge

Projection electroscope connected by red alligator clip lead to one of two copper spheres on Teflon supports on a wooden base; white charging rod, black felt pad, and proof plane in foreground

Charging by Induction

Demonstrates electrostatic induction using two copper spheres on Teflon supports. A charged sphere induces charge separation in a nearby neutral conductor; the projection electroscope and proof plane verify that the …
Two brass hemispheres on horizontal rods in cross clamps on black ring stands, flanking a small brass sphere on a glass insulating stand; proof plane, charging rod, and charging pad in foreground

Induction Hemispheres

Demonstrates that charge on a conductor resides entirely on its outer surface. A charged sphere is surrounded by conducting hemispheres; the proof plane and electroscope show the outer surface carries …
Needle electroscope with metal sphere on top and needle inside circular ring frame on white cylindrical base; white Teflon rod, clear acrylic rod, gray felt and white cloth charging pads at left; CENCO grounding stand with red alligator clip at right

Induced Charge on Electroscope

Demonstrates charging by induction using a needle electroscope. A charged rod induces charge separation; grounding while the rod is nearby permanently transfers charge of the opposite polarity. Test the sign …
Charging rods (white Teflon rod and clear glass rod) with fur and silk charging materials, alongside a Pepsi aluminum can

Rolling Can

Demonstrates electrostatic induction in conductors. A charged rod induces charge separation in a neutral aluminum can, causing the can to roll toward the rod regardless of the rod's polarity. Addresses …
Hand holding inflated purple balloon above a watch glass containing small white foam confetti pieces
Safety

Balloon and Confetti

A charged balloon attracts neutral paper confetti via polarization and picks up oppositely charged foam confetti via Coulomb attraction. Deflating the balloon while maintaining its charge increases surface charge density, …
One red balloon adhering to a wooden door frame and two clear balloons stuck to a chalkboard surface, demonstrating electrostatic adhesion

Balloon on a Wall

A charged balloon sticks to a neutral wall through electrostatic induction. The electrostatic attraction between the balloon's charge and the induced surface charge in the wall easily overcomes the gravitational …
Black acrylic board on green lab mat with "Charge it up" written in white chalk dust. Grounded wire mesh with handle above, folded white silk cloth at top right, yellow cloth at bottom left.

Electrostatic Imaging

Demonstrates triboelectric charging and electrostatic imaging. Rubbing silk on an acrylic board deposits a localized charge pattern; dusting with chalk reveals the pattern because neutral chalk particles are attracted to …
Blurred 2×4 rotating on green platform atop wooden stand, hand holding white charging rod near one end of the board

2 x 4 Electroscope -- Versorium

A 6-foot 2x4 balanced on an inverted watch glass rotates to follow a charged rod, demonstrating that charged objects attract neutral objects regardless of charge sign. Dramatically illustrates electrostatic induction …
Hand holding a white charging rod near a thin water stream from rubber tubing clamped to a stand over a sink, with shadow projection visible on the wall behind showing the deflection
Safety

Charged Rods and Water

A thin stream of water deflects toward both positively and negatively charged rods, demonstrating that the attraction is due to the polarity of water molecules rather than any net charge …
Kelvin water dropper with clear acrylic frame and water reservoir on top, two copper collection cans below with cross-connected induction rings, and separate ring-shaped spark gap electrodes on stands to either side
Safety

Kelvin Water Dropper

Falling water droplets separate charge through electrostatic induction, demonstrating how a positive feedback loop amplifies tiny charge imbalances to generate kilovolts without any external power source. Gravitational potential energy converts …