Magnetic Basics
What is the invisible area around a magnet where magnetic forces are felt called?
Magnetic field
What can you sprinkle on paper to reveal magnetic field lines?
Iron filings
What is the dependent variable in an experiment testing how magnets move paperclips at different distances?
How far or fast the paperclip moves
What do magnetic field lines connect?
North and South poles
Why does a magnet stick to a fridge door but not to a wooden cabinet?
Only magnetic materials (like steel in the fridge) attract magnets
What are the two poles of a magnet?
North and South
What makes a paperclip stick to a magnet even though it’s not normally magnetic?
It becomes a temporary magnet
Can a one-pole magnet exist? Why or why not?
No. Cutting a magnet creates two smaller magnets with both poles
What do arrows on magnetic field lines show?
The direction of the force
Why does a phone case sometimes mess up a compass app?
Some cases have magnets that interfere with the phone's sensor
What happens when like poles are pushed together?
They repel
What happens to magnetic force as the distance between magnets increases?
It gets weaker
Name one way to demagnetize a magnet.
Heat it, hit it, or expose it to another strong magnetic field
Where are field lines the most concentrated?
Near the poles
Why are headphones and speakers made with magnets inside?
Magnets help turn electrical signals into sound by moving a speaker cone
What type of magnet only works when electricity flows through it?
Electromagnet
What real-world transportation system uses magnetic repulsion to float?
Maglev train
What part of Earth creates its magnetic field?
The molten iron and nickel in Earth’s outer core
What causes the shape of the field lines to change?
Repelling or attracting forces between magnets
How do security tags in stores use magnets to prevent theft?
Magnetic locks hold the tag in place until deactivated at checkout
Why do magnets only attract certain materials like iron, nickel, and cobalt?
Because those materials have atoms with magnetic domains that can align
Two identical magnets are placed at different distances from a paperclip. One makes the paperclip move, the other does not. Why might this happen?
The magnetic force gets weaker with distance—one magnet is too far to exert a strong enough force.
How can you tell if a material is non-magnetic?
It does not attract to a magnet and its magnetic domains are not aligned
Why are field lines spaced further apart in weaker areas?
The force is weaker where lines are farther apart
Why do some trains float above the tracks without touching them?
They use magnetic repulsion (like poles) to levitate and reduce friction