Unit 2 Science STUDY GUIDE!

Proton

Proton

This is the positive particle found inside an atom

Magnetic Domains

These are what line up at the atomic level in order to make a material magnetic

Ferromagnetic

Any material that attracts iron or materials containing iron.

Neutron

This is the neutral particle found in the atom

Magnetic Field

A region around a magnetic object where another magnetic object would experience a push or pull

Current

This is the rate at which electrons pass a given point per second

Electric Field

This is the region around a charged object that another charged object would experience a push or pull

Voltage

This is the push behind the electrons in a circuit that can be produced using a battery.

Static Electricity

This is the buildup of charges that are stationary on the outside of objects.

Electromagnet

This is a coil of wire wrapped around a soft iron core that acts like a magnet when an electric current is applied.

Ampere

This is the unit for measuring current

Resistance

This is what is created when electrons rub against the atoms in the wires of a circuit.

Ohm

This is the unit for measuring electrical resistance

Electromagnetic Induction

This is the process of making electrons move in a coil of wire by either moving a magnet near the coil of wire or moving the coil of wire near a magnet.

Electron

This is the negative particle found in the atom

A magnet is any piece of material that has the property of attracting _____

Iron

All magnets have a…

North & South Pole

Same/Like poles…..

Repel/push away from each other

In order for a material to be magnetized, the material must contain….

MAGNETIC DOMAINS

Materials that can be magnetized are called….

Ferromagnetic Materials

What are ferromagnetic materials?

Iron, Cobalt, Nickel

When ferromagnetic materials are exposed to a really strong magnetic field, their……

Magnetic Domains line up

Magnetism is a….

Noncontact force

The strength if the magnetic force between two magnets depend…..

On the strength of each magnet and the distance between the two magnets.

As two magnets get further apart, the magnetic force between the two will….

decrease

Electric Charge is

A property of matter

An object is either.....

Positive, Negative, or Neutral

All matter is made up of.....

Atoms

Atoms have…

3 smaller particles in them.

Protons have a…

Positive Charge

Electrons have a…

Negative Charge..

Neutrons have…

NO CHARGE (NEUTRAL)

Protons and Neutrons are held tightly in the center of the atom called the....

Nucleus

Electrons are located....

Outside the nucleus

Atoms are usually....

…Neutral…

Atoms have the....

Same number of electrons

Atoms become charged by….

Gaining or Loosing Electrons

Any material that GAINS electrons will become…..

Negative

Any material that LOSES electrons will become...

Positive

Charged objects will exert an...

Electric Force

Electric Forces are…

Noncontact forces

Objects with opposite charges….

Attract

Objects with Like/Same Charges….

Repel

The strength of the electric force between two charged objects depends on.......

The amount of charge built up on each object and the distance between the objects.

The electric force ______ as more charges build up on both objects

increases

The electric force _____ as the objects get further apart.

decreases

Sometimes when two neutral objects are rubbed together, the FRICTION between the two objects will cause the ___________ to move from one of the objects to the other.

electrons

Usually, the natural material will ____ electrons and become ___________ charged.

Loose, Positively

The synthetic material will ____ electrons and become __________ charged.

Gain, Negatively

A charged object sometimes transfers charges to the surface of a neutral object when they touch. This is called charging by......

Conduction

Sometimes, charges could be rearranged within a neutral object when a charged object is brought near it but does touch it. This is called charging by....

Induction

Example of induction….

Induction happens in a wall when a charged balloon is brought near it.

Charges that build up on a material will slowly move to the surrounding air molecules or they may move suddenly. This is called an electric....

Discharge

The law of Conservation of charge states.....

The amount of electric charge in the Universe remains constant. Charges CANNOT BE created or DESTROYED! They simply move from one place to another.

An attracting force occurs between two objects that

Have opposite charge

When Bethany walks across a carpet, her socks pick up many electric charges. Later in the day, these charges are no longer present on her socks. What most likely happened to the charges?

The charges transferred to another object

During a lightning storm, the bottom of a cloud gains a strong negative electric charge which induces a strong positive charge on the surface of the earth. When this happens, tons of charges will move. This movement of charges is called…

Electric Discharge

Which statement describes the force that is exerted on the objects below due to their electric charge?

There is a force pushing the objects away from each other

Most materials have a net neutral charge because of the number of…

Positive charges are equal to the number of negative charges

The diagram shows two pairs of charged objects. Based on the diagrams, which statement is true

The strength of the electric force between A and B is greater than C and D because they are closer together.

When 2 pieces of clothing tick”to each other after taking out of the dryer, the clothes must…

Have opposite charges

What happens when a rubber rod is rubbed with a piece of rabbit fur?

Electrons are moved from the fur to the rod

When rubbing your hair with a balloon, the hair

Loses electrons and becomes positive

How does a charged balloon ¨stick” to a wall?

The negatively charged balloon caused the negative charges in the wall to repel, leaving a net positive charge on the surface of the wall which caused the balloon to “stick” to the wall

Most materials have no charge because the

Number of electrons are equal to Number of Protons

The law of Conservation of Charge says that the charges in a system..

Remain the same, cannot be created or destroyed, are simply transferred from one area to another.

What hypothesis does the data in the chart support?

More rubs creates more electric force which causes the balloons to repel from a greater distance

The electrons are…

Attracted to the nucleus

Electric force is a…..

Noncontact force, both a repulsive and attractive force

The rate at which electric charges move THROUGH a wire in a closed circuit  is called what?

Electric current

What is the unit for current?

Ampere (A)

What is the unit for voltage?

Volt (V)

Resistance is measured in

Ohms ( Ω )

If voltage is increased, current will

increase

If resistance increases, the current will

decrease

Resistance in a really skinny wire could produce

heat

What is Ohm’s Law?

Current (I) = Voltage (V) / Resistance ( R )

What is created around the outside of a wire when electric current is flowing through the wire?

A magnetic field is generated.

What are 3 ways to increase the strength of an electromagnet?

Increase the current, increase the # of coils, add an iron core. 

The electric motor converts electrical energy into what kind of energy?

Kinetic Energy

The electric generator converts kinetic energy into what kind of energy?

Electrical Energy

The electric generator generates an electric current by moving a coil of wire inside a permanent magnet.  What is the name of this process?

Electromagnetic induction

The magnetic field of an electromagnet can be easily reversed by doing what?

Reversing the current that flows through the coil.

A compass has a magnetic needle.  So what would happen if a wire with current flowing through it was brought near it?

The compass would wiggle because the current in the wire would create a magnetic field and the magnetic needle of the compass would react to it.

In the electric motor, why does the electromagnet spin inside the permanent magnet?

The electromagnet spins to line up with the opposite poles of the permanent magnet.

What part in the motor is used to reverse the current quickly?

Commutator

The electricity in a generator only flows if either the magnet or the coils of the wire are…

Moving

In a power pant that uses generators to make electricity, what are 3 different ways to spin the generator?

Water, Wind, Nuclear, Burning Fossil Fuels

A big advantage of electromagnets compared to permanent magnets is that the magnetic field of an electromagnet….

Can be turned on and off, Can be reversed, And can be increased and decreased easily.

Which of the following would increase the strength of an electromagnet

Increasing the number of coils and increasing the current

What creates the magnetic force around a copper wire carrying current?

The electricity flowing through the wire, and the electrons flowing through the wire.

The unit for measuring current is…..

(AMPERE)

Which of the following devices uses electromagnet induction to create elecricity

Generator

A generator…

Moves magnets near coils of wire to convert kinetic energy into electrical energy.

What happens to the magnetic field of an electromagnet when the current flowing though it is reversed

The magnetic field reverses

What causes the electromagnet in a motor to spin

The electricity creates a magnetic field around the electromagnet which interacts with the permanent magnetic field.

Josie wants to test to see if the battery below is still working. She wraps a wire around a compass and connects each end to the battery as shown in the diagram. Would this method work to tell if the battery is still good?

This method of testing batteries would work because if the battery is good, current will flow through the wire creating a magnetic field that would interact with the magnetic field of the compass needle and make it move.

The electric motor converts…..

Electrical energy into Kinetic enrergy.

Nadia created an electromagnet by connecting 100 coils of wire to a battery. It was able to pick up 10 paper clips. She wanted to increase the strength of the magnetic field so she added a metal core but the magnetic field still only picked up 10 paper clips. Why could this be?

The metal core was not made of iron, nickel, or cobalt

In order to create a magnetic field around a wire using electricity…..

You must have a closed loop, and must have a voltage source