Electricity Chapter 11
Home > Flashcards > Print Preview
The flashcards below were created by user
on FreezingBlue Flashcards
. What would you like to do?
- A closed path along which electrons that are powered by an energy source can flow.
- This can take the form of a circuit board, loads wired together, the wires in your house, and even something as large as the power grid.
- 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.
- Some common types would be: Zinc-Carbon, Alkaline, Lead-Acid, Silver-Oxide, etc.
- A connection of two or more cells.
- When you place two AA "Batteries" (which are really cells) in a flashlight you make a battery.
- One of two metal terminals in a cell or battery.
- They must be made of different metals with different holds onto electrons so the electrons know which way to flow.
- A solution or paste that conducts charge.
- The electrolyte separates the two electrodes and the chemical reaction that takes place to move electrons happens within the electrolyte.
- A cell that contains an electrolyte that is a paste.
- Some common dry cells would be Zinc-carbon and Alkaline.
- A cell that contains a liquid electrolyte.
- An example would be a lead-acid battery.
- A cell that can only be used once.
- Some examples would be Zinc-Carbon and Alkaline.
- A cell that can be recharged.
- Some common types would be lead-acid and lithium-ion.
- A cell that generates electricity through the chemical reactions of fuel that is stored outside the fuel cell.
- An example would be a hydrogen fuel cell that combines hydrogen and oxygen to make water, heat, and electricity.
A cell that converts sunlight into electrical energy.
- The location on a cell that must be connected to other components to form a circuit.
- Both the positive terminal and negative terminal must be connected to the circuit to complete it.
- Electrons flow from the negative terminal to the positive terminal.
- A control device that can complete or break the circuit to which it is connected.
- This is useful because circuits don't have to be on all the time if you have a switch.
- A circuit that contains a gap or break.
- An open circuit can not function since there is no complete path for electrons to travel along.
- Hitting a switch or button on a lamp or TV can open or close a circuit.
- The rate of movement of electric charge (flow of electrons).
- An analogy would be to think of how many m3 of water flow by in a river per second.
The quantity of charge that is equal to the charge of 6.25 * 1018 electrons.
- The unit of electric current, equivalent to one coulomb per second.
- An ammeter measures the amount of current in one location of a circuit in amperes.
- The property of a substance that hinders electric current and converts electrical energy to other forms of energy.
- Some materials have lower or higher resistances than other materials.
- Materials with lower resistances are conductors while materials with very high resistances are insulators.
- A devices used in an electric circuit to decrease the current through a component by a specific amount.
- These are useful to ensure that components in a circuit don't get too much energy and break.
- A resistor or any other device that transforms electrical energy into heat, motion, sound, light, or other forms of energy.
- Some examples would be: a speaker, a light a bulb, a motor, a stove, etc.
Potential difference (voltage)
The difference between the electric 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).
- The equation to find potential difference is:
- potential difference = difference in potential energy (J) / charge (C)
- A diagram that uses standard symbols to represent the components in an electric circuit and their connections.
- Some standard symbols are that two parallel lines of different length represent a cell, straight lines are connecting wires, and a switch is a portion of the wire that looks swivelled open.
- A circuit in which there is only one path along which electrons can flow.
- If a series circuit is broken at any point then the whole circuit will stop functioning.
- A circuit in which there is more than one path along which electrons can flow.
- Parallel circuits can be broken and any path not affected by the break can still function.
- The ratio of potential difference to current is a constant called resistance.
- The equation is written as V=IR
- Thus the more resistance in a circuit, the less current since they is more resistance to the movement of electrons and the movement of electrons is current.
- The unit for resistance, equivalent to one volt per ampere (V/A).
- If you substitute in potential difference and current measurements into the equation V=IR you can find the resistance in ohms.
- All loads in a circuit increase the resistance of a circuit.
- A material through which electric charge can flow with no resistance.
- An example of a superconductor is when the wires in the CERN supercollider are cooled to a few degrees above zero with liquid helium.
- Not following Ohm's law.
- An incandescent light bulb filament is non-ohmic since the filament increases in temperature which increases the resistance and produces a non-ohmic energy curve.
Loads in series
- In a series circuit the potential difference across the cell must equal the sum of all the potential differences across all of the loads.
- VT = V1 + V2 + V3 + ...
- The current of through the battery is equal to the current through all the loads.
- IT = I1 = I2 = I3 = ...
Loads in parallel
- In a parallel circuit the potential difference across the cell is equal to the potential differences across of the loads.
- VT = V1 = V2 = V3 = ...
- The current total current must be equal to the sum of all the currents through all the paths.
- IT = I1 + I2 + I3 + ...
What would you like to do?
Home > Flashcards > Print Preview