Electricity Chapter 11

• A closed path along which electrons that are powered by an energy source can flow.
• Eg. Lamps have an electrical current, a wire runs from the battery to the bulb and the bulb converts the electrical energy into heat energy.

• A source of energy that generates an electric current by chemical reactions involving two different metals or metal compounds separated by a solution that is a conductor.
• Eg. AAA, AA, C, or D "batteries" are voltaic cells.

• A connection of two or more cells.
• Eg. When you put two or more cells into a flashlight.

• One of two metal terminals in a cell or battery.
• Eg. Copper or aluminum

• A solution or paste that conducts charge.
• Eg. Lemon juice is an electrolyte.

• A cell that contains an electrolyte that is a paste.
• Eg. Zinc-carbon cell, alkaline cell, silver-oxide cells, zinc-air cells.

• A cell that contains a liquid electrolyte.
• Eg. Lead-acid battery used in trucks, automobiles, and motorcycles.

• A cell that can be used only once.
• Eg. Any cell that is not reusable.

• A cell that can be recharged.
• Eg. Any cell that is rechargeable.

• A cell that generates electricity through the chemical reactions of fuel that is stored outside the cell.
• Eg. Fuel cells are used for automobiles, buses, and small devices.

• A cell that converts sunlight into electrical energy.
• Eg. Small solar cells can provide energy for a calculator or ornamental garden light, large solar cells can operate a communications satellite.

• Location on a cell that must be connected to other components to form a circuit.
• Eg. The ends of a battery, the positive and negative terminals on a ammeter and voltmeter.

• A control device that can complete or break the circuit to which it is connected.
• Eg. a light switch, on/off button.

• A circuit that contains a gap or break.
• Eg.

• The rate of movement of electric charge.
• Eg. The flow of electrons.

The quantity of charge that is equal to the charge of 6.25 x 10¹⁸ electrons.

• The unit of electric current, equivalent to one coulomb per second.
• Eg. Can be measured using an ammeter.

• The property of a substance that hinders electric current and converts electrical energy to other forms of energy.
• Eg. The type of wire, the temperature of the wire, thickness of the wire, and types of loads have and effect on the electrical resistance.

• A device used in an electric circuit to decrease the current through a component by a specific amount.

• A resistor or any other device that transforms electrical energy into heat, motion, sound, or light.
• Eg. Lightbulb, oven, hairdryer, dishwasher.

• The difference between the electrical potential energy per unit of charge at two points in a circuit.
• Eg. Can be measured using a voltmeter.

The unit for potential difference, equivalent to one joule (J) per coulomb (C).

A diagram that uses standard symbols to represent the components in an electric circuit and their connections.

A circuit in which there is only one path along which electrons can flow.

A circuit in which there is more than one path along which electrons can flow.

• The ratio of potential difference to current is a constant called resistance.
• Eg. V=IR, I=V/R, R=V/I, potential difference = current x resistance

The unit for resistance, equivalent to one volt per ampere (V/A).

• A material through which electric charge can flow with no resistance.
• Eg. Mercury is a superconductor when it is the temperature of liquid helium.

• Not following Ohm's law.
• Eg. The filament of an incandescent bulb is non-ohmic because the resistance increases with temperature.

When two or more loads are on one path in a circuit. The potential difference goes through all of the loads. The current is the same throughout the circuit because it only goes through one path.

When two or more loads are in the same circuit but are on different paths. The potential difference will separate down each path, going down a path that is the quickest way back to the battery or separating so that each load on each path has enough volts. The current slows down at each path depending on the resistance of the loads.