Magnetism
Describe the force between two opposite poles of magnets.
The force is attractive.
How can you tell if an object if positively charged?
It has more positive charges than negative charges.
Arrows around a planet represent what?
The gravitational field of that planet
Kim has a loop of wire and a magnet. How could she induce a large electric current in the wire?
She could move the magnet quickly through the loop of wire.
What area of a bar magnet has the strongest magnetic force?
When a cloth is rubbed against a balloon what happens to the charges?
Negative charges from the cloth are transferred to the balloon.
Emilio is using a compass to investigate magnetic forces. Would a wire he is using to charge his cell phone affect compass?
Yes, because the electric current going through the wire creates a magnetic field.
What happens to the magnetic domains when a magnet is cut in half?
The magnetic domains of both halves still point in the same direction.
How do the magnetic domains point in a magnet?
All in the same direction. This is what causes iron to be magnetic.
How is the electric force between charges similar to the magnetic force between magnets?
Opposite charges attract each other, similar charges repel each other.
How are distance and the strength of noncontact forces related?
As distance decreases the strength of the force increases
If I needed to pick up a metal object and drop it would I use a permanent magnet or an electromagnet? Why?
An electromagnet because the it can be turned on to pick up a metal object and turned off to drop that metal object.
When a ferromagnetic material is brought close to a non-magetic material what direction will the domains face?
The domains will face in all directions b/c the non-magnetic materials does not affect the domains.
If I doubled the amount of charges in a space how would that affect the amount of field lines?
The amount of field lines would also double and the field would be stronger.
Define criteria and constraints.
Criteria are things we want our solution to have. Constraints are obstacles to our solution.
How does changing the direction of a current affect the magnetic force in an electromagnet?
The magnetic field is reversed. The north pole would become the south pole and vice versa.