science quiz 7

marusich gt

electric current

A flow of electric charge. The higher the current, the more charge that passes through it.

potential difference

energy per unit (expressed in volts)

resistance

opposition to electric current in circuit measured in Ohms (ex: resistors or loads in circuits)

the electric current exists because

a chemical reaction causes a difference in charge between 2 electrodes

electrodes

a conductor that electricity enters through

good conductors have low resistance, bad conductors have

high resistance.

thick wires have less resistance because

thick wires don't block the current as much, there is more space for the electricity to flow

in high temperatures, atoms move faster, causing more or less resistance to the flow of electric charges?

more resistance

turning on the electric current sets up...

an electric field. this causes free electrons in the wire to "charge ahead" (individual electrons move very slowly)

Negatively charged objects attract....

positively charges objects OPPOSITES ATTRACT, LIKES REPEL (charges DON'T need to be touching to repel or attract after being charged by friction)

Electric charge is caused by

electrons

How do objects get charged

when they transfer or remove electrons. static discharge happens when the built up charges overflow.

increasing resistance with constant voltage increases or decreases the current?

decreases the current

Increasing voltage with constant resistance increases or decreases the current?

increases the current

Does voltage have an effect on resistance?

no, they are separate factors

insulator

something that resists the flow of electrons (ex: rubber)

conductor

something that lets electrons flow easily (ex: copper)

static electricity

A buildup of charges on an object. (ex: lightning, getting shocked from a doorknob after friction) unbalanced charges, movement of charges

Conduction

one object comes in contact of another, causes electrons to be passed from an object to another (ex: getting shocked from an object)

induction

one object comes close to another, causing electrons to rearrange on the other object (ex: hair going towards the balloon in the balloon experiment)

the greater the voltage the greater the current. The greater the current, the more....

charge that passes through a point

amp

The unit of current; also known as the ampere

how the current and voltage are related

current depends on voltage, the greater the voltage, the greater the current

in a circuit, what are common conductors that are used

wires

in a circuit, what is a load

a device that converts electrical energy into another form, like light from a light bulb

what is an electric circuit

a complete closed path for electrons to flow, flow begins and ends in the same energy source

what types of circuits are there?

simple, parallel, series, combined

simple circuit

one of each required part connected together (note: when drawing the circuit, use the symbols)

parallel circuit

A circuit that contains more than one path for current flow, pathways share the same voltage (if one load gets disconnected the others keep working because they have their own pathways)

Combined circuit

A mix between a series and parallel circuit, its like have a series circuit on each branch of a parallel circuit.

series circuit

basically like a simple circuit, but with more than one load

Magnetism

The force of attraction or repulsion of magnetic materials.

What happens if the North is facing the North on two bar magnets?

They will repel

What happens if the South is facing the North on two bar magnets?

They will be attracted to each other

What materials are ferromagnetic?

Iron and nickel

Do magnets have to touch to be attracted or repelled?

No, some magnets are stronger the closer they are to the material, but they don't need to touch.

What does a switch do in a circuit?

Opens/closes the path of the electrons to stop them from flowing or to make them continue flowing

Can you magnetize a metal with a magnet?

Yes

what is an open circuit

It is when a circuit is incomplete due to a gap or a break in the circuit.

what is a closed circuit

A closed circuit is complete and unbroken.