Magnetic field lines go from ____________ to ____________ outside a magnet.

• north to south

• south to north

• positive to negative

• left to right

Magnetic fields are created by:

• Stationary electric charges only

• Only bar magnets

• Moving electric charges and magnetic materials

• Sunlight hitting metal

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What happens to a magnetic field if the current in an electromagnet is reversed?

• It disappears

• The magnetic field gets stronger

• The direction of the magnetic field reverses

• Nothing changes

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Why do magnetic field lines never cross?

• They are just drawings and don’t matter

• They represent the temperature of magnets

• A magnetic field can only have one direction at a point in space

• They’re blocked by electric fields

What strengthens an electromagnet?

• Decreasing the number of coils

• Wrapping wire into a straight line

• Adding an iron core and more current

• Using fewer electrons

What allows maglev trains to move without touching the track?

• Wheels with magnets

• Magnetic levitation from repelling forces

• Compressed air under the train

• Rocket boosters

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Which is NOT an advantage of maglev trains?

• Less noise

• Lower friction

• Use of fossil fuels

• Smoother rides

What makes maglev systems expensive to build?

• Train drivers earn high salaries

• The train cars are heavier

• Special tracks and strong magnets are costly

• They need water cooling systems

How do engineers control the speed of maglev trains?

• By adjusting fuel levels

• By reversing and changing the strength of magnetic fields

• By rotating the wheels faster

• By adding more train cars

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Which of the following is always magnetic and does not require electricity?

• Electromagnet

• Permanent magnet

• Magnetic coil

• Battery