1 / 50

# Magnetism - PowerPoint PPT Presentation

Magnetism. Observe:. N. S. N. S. Attract or repel?. Observe:. S. N. N. S. Attract or repel?. Observe:. N. S. S. N. Attract or repel?. Observe:. N. S. N. S. Attract or repel?. Observe:. N. S. Make a map of the magnetic field around the bar magnet. N. S.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.

## PowerPoint Slideshow about 'Magnetism' - tamira

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

### Magnetism

N

S

N

S

Attract or repel?

S

N

N

S

Attract or repel?

N

S

S

N

Attract or repel?

N

S

N

S

Attract or repel?

N

S

What does the current in the wire do?

I

I

B

B

• This is called the right hand rule

• If you put a ______ in a __________ field, it will experience a force.

• If you put a ______ in a __________ field, it will experience a force.

• If you put a mass in a gravitational field, it will experience a force.

• If you put a ______ in a __________ field, it will experience a force.

• If you put a mass in a gravitational field, it will experience a force.

• If you put a charge in an electrical field, it will experience a force.

• If you put a ______ in a __________ field, it will experience a force.

• If you put a mass in a gravitational field, it will experience a force.

• If you put a charge in an electrical field, it will experience a force.

• If you put a magnetin a magnetic field, it will experience a force.

Electrical and magnetic fields can attract and repel.

Gravitational fields seem to only attract

A moving charge affects a magnet

A moving magnet affects a charge

A moving charge affects a magnet

… it makes a magnetic field

A moving magnet affects a charge

… it makes an electrical field

A moving charge affects a magnet

… it makes a magnetic field

A moving magnet affects a charge

… it makes an electrical field

• There is an application of the right hand rule for each of these

A stable magnetic field affects a charge…

A stable electrical field affects a magnet…

A stable magnetic field affects a charge…

… only if the charge is moving

A stable electrical field affects a magnet…

…only if the magnet is moving

A stable magnetic field affects a charge…

… only if the charge is moving

A stable electrical field affects a magnet…

…only if the magnet is moving

• There is an application of the right hand rule for each of these

• A coil of wire, carrying a current makes a magnetic field.

• If you put the coil around a piece of iron or steel, it becomes an electromagnet.

• A coil of wire, carrying a current makes a magnetic field.

• If you put the coil around a piece of iron or steel, it becomes an electromagnet.

• Where could you use an electromagnet?

If a magnet can move into and out of the coil, it is called a solenoid.

If a magnet can move into and out of the coil, it is called a solenoid.

• Where could you use a solenoid?

• An electric motor converts electrical energy into work, usually rotational motion.

• Usually, a magnet makes coil of wire rotate when a current is flowing.

• Use the right hand rule !

• F = force on the wire =palm

• I = the (+) current =thumb

• I = the (+) current =thumb

• B = the magnetic field =index finger

What is the missing vector ?

I

B

What is the missing vector ?

I

B

Mechanical Energy Electrical Energy

Motors

--Convert electrical energy into mechanical energy

--An electric current causes a coil of wire to spin in a magnetic field

--The rotational motion can do many jobs

Mechanical Energy Electrical Energy

Generators

--Convert mechanical energy into electrical energy

--A coil of wire spinning in a magnetic field causes an electric current

--There are many ways to spin the generator

Mechanical Energy Electrical Energy

Motors

--Convert electrical energy into mechanical energy

--An electric current causes a coil of wire to spin in a magnetic field

--The rotational motion can do many jobs

Generators

--Convert mechanical energy into electrical energy

--A coil of wire spinning in a magnetic field causes an electric current

--There are many ways to spin the generator

2

3

4

5

6

Mechanical Energy Electrical Energy

Generator: If you move the wire, the force is exerted on the charge

Motor: If you move the charge (a current), the force is exerted on the wire

• I

• B

• B

• EMF

• Force

• EMF = force on the charge

• =palm

• v = velocity of moving wire =thumb

What is the missing vector ?

v

B

What is the missing vector ?

v

B

What is the missing vector ?

EMF

v