1
What is a magnet
Any object that has magnetic force
How many poles does Earth have? Name them
4. Magnetic north and south. Geographical north and south
When can you switch a magnet on and off?
If it is an electromagnet
What is the earth's core made of?
Hot, liquid iron
What is a permanent magnet
An ovject that always has a magnetic force that cannot be turned off
What is an induced magnet?
Only gives off a magnetic force for a period of time
How can you observe a magnetic field?
Lay iron filings on a surface and place a magnet in the middle
What does the earth's magnetic field protect us from?
Harmful UV rays, space radiation, and particles from solar wind
What is the inner circle of a compass called?
Cardinal Rose
Can magnetic force overcome gravity? Give an example
Yes, especially with electromagnets
Why are extremely powerful electromagnets useful?
they can overcome gravity
How can I tell if a piece of jewelry is fake using a magnet?
If the jewelry was real gold or silver it will NOT be attracted to a magnet
Will a non magnetized bar of iron repel from a magnet?
No because the non magnetized bar has no poles
What is an electric current?
Electrons move through a wire to create a magnetic field. These wires can repel and attract
If a magnet's charges move more, what happens?
The magnet's strength increases
What is a magnetic field
Invisible and the area that fills a space where a magnetic force works. Produced by magnetic charges
Given only a magnet you know is real, and a piece of iron, how can you tell if the bar is magnet or not?
If the bar repels the magnet
Exaplin how the electromagnet in a doorbell works
Doorbell is pressed which closes an electric current
Electric current flows and creates a magnetic field
The electromagnet attracts a metic arm which makes a sound
Metal arm moves out of position and the circuit opens
Electromagnet turns off
Now it's back to its original state
Why are Earth's geographic and magnetic poles different?
because the liquid iron in earth's core is moving
How does an electromagnet work?
Using electricity, you force electrons to move in the same direction.