Electromagnetism Test Review – Flashcard Assignment

What is magnetism?

• Magnetism is a fundamental force that relates to iron and other materials.

• Magnetism is a type of sound wave that travels through air.

• Magnetism is the process of converting water into steam.

• Magnetism is a method of measuring temperature.

What does an electron orbiting or spinning create?

• An electron orbiting or spinning creates a magnetic dipole.

• An electron orbiting or spinning creates a gravitational wave.

• An electron orbiting or spinning creates a sound wave.

• An electron orbiting or spinning creates a chemical bond.

What happens when many atoms’ magnetic fields align in the same direction?

• When many atoms’ magnetic fields align in the same direction, they form magnetic domains, which create stronger magnets.

• The atoms lose their magnetic properties completely.

• The atoms start to vibrate rapidly, producing heat.

• The atoms become electrically charged and repel each other.

What are magnetic lines of force?

• Magnetic lines of force are invisible lines that represent the direction and strength of a magnetic field.

• Magnetic lines of force are visible lines that can be seen with the naked eye around a magnet.

• Magnetic lines of force are electric currents flowing through a wire.

• Magnetic lines of force are the physical wires connecting two magnets.

Draw and explain how they flow outside (N → S) and inside (S → N) a magnet.

• Magnetic field lines flow from the north pole to the south pole outside the magnet and from the south pole to the north pole inside the magnet.

• Magnetic field lines flow from the south pole to the north pole outside the magnet and from the north pole to the south pole inside the magnet.

• Magnetic field lines flow in a circular motion both inside and outside the magnet.

• Magnetic field lines do not have a specific direction inside or outside the magnet.

How is magnetic field strength related to flux density?

• More lines of flux mean a stronger magnetic field.

• Fewer lines of flux mean a stronger magnetic field.

• Magnetic field strength is unrelated to flux density.

• Flux density decreases as magnetic field strength increases.

What unit measures magnetic flux density? What is the value of Earth’s magnetic field?

• The unit is Tesla (T); Earth's field is approximately 0.0001 T.

• The unit is Newton (N); Earth's field is approximately 1 T.

• The unit is Ampere (A); Earth's field is approximately 0.01 T.

• The unit is Joule (J); Earth's field is approximately 0.1 T.

What is a natural magnet? What is an artificial magnet like alnico?

• A natural magnet is lodestone; an artificial magnet is alnico (steel alloy).

• A natural magnet is alnico; an artificial magnet is lodestone.

• A natural magnet is steel; an artificial magnet is iron ore.

• A natural magnet is copper; an artificial magnet is nickel.

What happens to an electromagnet’s field when current stops?

• The field disappears; it is not permanent.

• The field becomes stronger.

• The field reverses direction permanently.

• The field turns into a magnetic wave.

What are the three laws of magnetism?

• Repulsion-attraction, magnetic poles, inverse square law.

• Coulomb's law, Ohm's law, Faraday's law.

• Newton's laws, Ampere's law, Lenz's law.

• Conservation of energy, Fleming's left hand rule, Gauss's law.