Electricity Basics Quiz

Study Notes

All matter is composed of tiny particles called atoms.
Atoms contain charged particles: neutrons, protons, and electrons.
Protons are positively charged.
Electrons are negatively charged.
Neutrons have no charge.
Electrons are negatively charged and orbit the positively charged nucleus (containing protons).
Static electricity is the buildup of stationary electric charges.
Static electricity often occurs on the surface of insulators.
Friction can cause static electricity. One material loses electrons and becomes positive, while the other gains electrons and becomes negative.
Neutral objects have equal numbers of protons and electrons.
Negatively charged objects have more electrons than protons.
Positively charged objects have fewer electrons than protons.
Charged objects can cause charge separation in neutral objects when brought close to them.
Electrical discharge occurs when built-up charges on one object transfer to another.
This creates a shock, often visible as a spark.
Electrons typically "jump" to the positively charged surface.

When a charged object is brought near a neutral object, it causes charge separation in the neutral object.
This creates an attraction between the opposite charges.

Lightning occurs when warm air rises above cool air.
The warm air condenses and releases energy.
Electrons transfer to raindrops, creating charges in clouds.
Bottom of clouds have a negative charge.
Top of clouds have a positive charge.
Positive charge is attracted to negative charge.
Lightning strikes are the discharge of electrons from a cloud to a positively charged surface (e.g., the ground).

A circuit is a complete path allowing electric current to flow.
Circuits often include switches, complete circuits, incomplete circuits, and cells.
A complete circuit has an unbroken path for current flow.
An incomplete circuit has an interruption.
A cell is a single unit that produces electric current.
The steady flow of charged particles is called electric current.

Ohm's law relates voltage, current, and resistance in a conductor. (V=IR)
Electrical power is the rate at which electrical energy is converted into another form like motion, heat, or light.
Formula: P=IV

Efficiency measures the useful energy output relative to the total energy input. (Efficiency = Energy Output / Energy Input×100%)
Formula: Efficiency = Useful Energy output/ Total Energy input x 100%