Chapter #11; Glossary Terms

• A closed path along which electrons that are powered by an energy source can flow.
• 

A source of energy that generates an electric current by chemical reactions involving two different metals or metal compounds seperated by conducting solution.

A connection of two or more cells.

• Battery symbol:
• 

One or two metal terminals in a cell or battery.



~ The breakdown of an electrode is one factor that can limit the life of a cell.

A solution or paste that conducts charge.

Example: Copper sulphate solution, and Sodium chloride solution.

A cell that contains an electrolyte made of paste.

Common household cells used in torches and remote controls are examples of dry cells.

A cell that contains a liquid electrolyte.

For example, a car battery.

A cell that can only be used once, like a disposable battery. 

A cell that can be recharged.

A cell that generates electricity through the chemical reactions of fuel that is stored outside the cell.

• ~ Hydrogen fuel cells combine hydrogen that is stored in a tank or cartridge with oxygen from the air.
• ~ By-porducts are heat and water.

A cell that converts sunlight into electrical energy. Multiple soalr cells form a solar panel. 

A position on a cell that must be connected to other components to form a circuit.

A control device that can complete or break the circuit to which it is connected.

A circuit that contains gaps or break.

Electrons do not flow through any part of the circuit where there is a gap or break, therefore opening a switch, which creats a gap, causes any device that is connected to the switch to stop working.

A measure of the number of charged particles that pass by a point in an electric circuit each second. 

• The quantity of charge that is equal to the charge of 6.25x10¹⁸ electrons.
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The unit of electric current, equivalent to one coulomb per second. Electric current is measured using an ammeter. 

The property of a substance that hinders electric current and converts electric enrgy to other forms of energy.

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.

The difference between the electrical potential energy per unit of charge at two points in a circuit.

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. 

Symbols: 

• Diagrams: 
• 

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




The same current flows through all the components, and if one component fails the circuit will not work.

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





The total current is the sum of the currents through each component. In a parallel circuit, the voltage across each of the paths is the same.

The ratio of potential difference to current is a constant called resistance. 

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

Symbol: 

A material through which electric charge can flow with no resistance.

Not following ohm's law.

For example, a light bulb.

• Current: 
• The current is the same at any point in a series connection.
• I_T= I₁= I₂=I₃

• Potential Difference:
• The potential difference across loads ins eries is the sum of the potential difference across all loads.
• V_T= V₁+ V₂+ V₃

• Resistance: 
• The resistance of loads connected in series id equal to the sum of the resistances of all the loads. 
• R_T= R₁+ R₂+R₃ 

• Current: 
• Current entering loads connected in parallel is equal to the sum of the current entering all the loads. 
• I_T= I₁+1₂+I₃

• Potential Difference:
• The potential difference is the same between the terminals of any load in a parallel circuit. 
• V_T= V₁= V₂ = V₃

• Resistance:
• The resistance of loads that are connected in parallel is less than the resistance of the smallest load. 
• R_T < R₁;  R_T < R₂;  R_T < R₃