Harder Magnetism

Magnetic field lines around a bar magnet

• are only perpendicular to the magnet.

• spread out from one pole and curve around to the other.

• cross back and forth over one another.

• are perfectly straight.

Every magnet, regardless of its shape, has two

• magnetic poles.

• magnetic charges.

• magnetic fields.

• magnetic needles.

Magnetic poles that are unlike

• attract each other.

• repel each other.

• do not interact.

• point in the same direction.

You can increase the strength of an electromagnet’s field by

• decreasing the current in the solenoid

• decreasing the number of loops in the solenoid.

• using a stronger ferromagnetic material for the core.

• winding the coils more loosely.

As Earth’s magnetic poles move, the magnetic declination in a given location will

• stay the same.

• switch to point south

• change

• return to zero.

An electric current produces a(n)

• magnetic field.

• magnet

• solenoid

• insulator

• electric field

A compass behaves as it does because the _____________ acts like a giant magnet.

• moon.

• earth.

• ocean.

• electromagnets.

Magnetic poles that are alike

• attract each other.

• repel each other.

• do not interact.

• point in the same direction.

A maglev train floats above its rails due to ____________________.

• magnetism

• currents

• voltage

• super conductivity

• steam

A(n) ____________________ is a strong magnet that can be turned on and off.

• electromagent

• dipole

• iron core

• solenoid