Forces and Fields
What observation provides direct evidence that magnetic fields act between objects that aren't touching?
The objects move toward or away from each other without touching.
When opposite poles face each other, magnets...
attract
What is an example of an electromagnet we saw in class (something only magnetic when energy is transferred through it)
Speaker, coil
Name something that can increase the amount of energy in a magnetic field
Shorter distance between parts, strength of forces
How does the distance between two magnets affect the magnetic force between them?
The force increases as the distance decreases or the force decreases as the distance increases
magnetic objects that are not permanent magnets usually move toward a magnet's ________ pole
South
The use of a weaker battery in an electromagnet may cause magnetism to...
This is evidence of a magnetic field being present
What happens to the potential energy when two magnets that repel get closer?
It increases
What factor is responsible for larger magnets having a larger magnetic field?
More material
When energy is added to an electromagnet, the electromagnet may
increase in magnetism
When magnets repel, potential energy increases as distance __________
decreases
Name two factors that affect the strength of a magnetic field
Distance, Material, size, exposure to certain conditions
One object we used to determine the direction of magnetic fields was...
Compass/Iron fillings
How might the distance of an electromagnet increase?
Add more energy or coils to system
When magnets attract, potential energy ____________ as distance increases
increases
When the distance of two magnets increases by 2 times, the strength of the magnet forces is weakened by ____ times. This is called the _______ __________ Law
4; inverse square
Name 3 things you can change to make a magnet move faster (not caused by applied force)
bigger magnet, reduce friction of surface, increase electric current, reduce air resistance
When an electromagnet has energy running through it, it acts as a permanent magnet. This can be said because...
The electromagnet has a north and south pole
Name two factors that could cause the magnetic field of a magnet to shrink
Heat, smaller, corrosion, distance