Lesson 4 Magnetism

A bar-shaped magnet generally produces its strongest effect at

• Its north pole

• Its south pole

• Both poles

• Its center

Two like magnetic poles always ___ each other.

• Attract

• Repel

• Cancel

• Reinforce

The earth's gravitational field pulls you down because you have

• Weight

• Mass

• Force

• Attraction

A magnetic field acts on other objects because the objects have

• Charge

• Mass

• Substance

• Magnetic properties

A moving charge creates a magnetic field. The strength of the field depends on the

• speed and strength of the charge

• distance between magnetic poles

• direction the charge is moving

• whether the charge is positive or negative

In both left-hand rules, your left thumb points in the direction

• in which the positive charges move

• in which the negative charges moves

• of the magnetic field

• of the north magnetic pole

A coil that carries an electric current is called a(n)

• Conductor

• Thermocouple

• Electrocurrent

• Electromagnet

One advantage of a lifting magnet is that it can lift

• Odd-shaped pieces

• All kinds of materials

• Other magnets

• With very little force

A magnetic chuck

• holds a tool in place

• should not be used near iron or steel

• is an electromagnet

• is a permanent magnet

Pieces of iron and steel can be removed from other materials on a belt by means of a

• Magnetic pulley

• Lifting magnet

• Magnetic chuck

• Metal separator