Vocabulary
A push or pull that can change an object’s motion.
Force
Two opposite magnetic poles face each other. What happens?
They attract (pull together)
What do magnetic field lines represent?
The strength and direction of the magnetic field.
What kind of energy is stored in a magnetic field?
potential energy
What type of energy does a moving object have?
Kinetic energy
What is a system?
A set of interacting parts forming a complex whole.
The space around a magnet where magnetic forces act
Magnetic Field
Two north poles face each other. What happens?
They repel (push apart)
Where is magnetic force generally stronger: near or far from a magnet?
Near the magnet.
When you move a magnet against a magnetic force, what happens to stored potential energy?
It increases
A spaceship speeds up. What happens to its kinetic energy?
It increases
What is a variable in an investigation?
Something that can be changed and may be measured.
One of the two opposite ends of a magnet.
Magnetic Pole
Can two magnets affect each other without touching? Explain.
Yes. Magnetic force acts at a distance.
How do field-line patterns differ for attracting and repelling magnets?
Attracting patterns connect between opposite poles; repelling patterns bend away between like poles.
You push two repelling poles closer together. What happens to potential energy?
It increases because you move against the repelling force
A magnetic force causes a cart to start moving. Which energy conversion occurs?
Magnetic potential energy converts to kinetic energy.
Why might scientists isolate one variable in a magnetic-force test?
To determine how that one variable affects the results.
A simplified diagram or object scientists use to understand a system.
Model
Two toy trains face each other with south poles nearest. Predict their motion.
They move apart because like poles repel.
What does it suggest when field lines are closer together?
A stronger magnetic field
You pull two attracting poles farther apart. What happens to potential energy?
It increases because you move against the attracting force.
When released, two repelling magnets move apart. What happens to kinetic energy as they speed up?
It increases as potential energy converts to kinetic energy.
A cart moves toward a fixed magnet, against a repelling force. Predict its potential-energy change.
Potential energy increases
A magnet whose magnetic field is produced by electric current.
Electromagnet
One magnet is N–S and another is N–S, placed end to end. Do the facing poles attract or repel?
They attract: the facing poles are S and N.
Describe the field-line pattern between two facing north poles.
The lines curve away from the space between the like poles; they do not connect directly across the gap.
Two identical carts move the same distance against magnetic forces of different strengths. Which movement adds more potential energy?
The movement against the stronger force
Explain why a magnet can gain kinetic energy without touching another magnet.
Magnetic forces act at a distance and can convert stored potential energy into motion.
Two identical magnetic cars start at different distances from a fixed magnet. Both are pushed one space against the same type of force. Which may gain more potential energy, and why?
The car closer to the magnet, because the magnetic force is stronger closer to it.