• Which part of an atom is positively charged, and which part is negatively charged?
• How does the charge of one electron compare with that of another electron?
• How do the masses of electrons compare with the masses of protons?
• What kind of charge does an object acquire when electrons are stripped from it?
• How is Coulomb's law similar to Newton's law of gravitation?
• How is Coulomb's law different to Newton's law of gravitation?
• How does the magnitude of electrical force between a pair of charged particles change when the particles are moved twice as far apart? Three times as far apart?
• What kind of force field surrounds an electric charge?
• What happens if an electric charge is placed in an electric field?
• In what way is the rule for the interaction between magnetic poles similar to the rule for the interaction between electric charges?
• In what way are magnetic poles very different from electric charges?
• What is the origin of all magnetic fields?
• What is a magnetic domain?
• Why is iron magnetic and wood not magnetic?
• In what ways can magnets lose their strength over time?
• Name two objects that create a magnetic field.
• What effect does the Earth's magnetic field have on the intensity of cosmic rays striking the Earth's surface?
• What are the three ways in which voltage can be induced in a loop of wire?
• How can a car moving along a paved road activate a traffic signal?
• What is the source of all waves?
• Distinguish between the period, amplitude, wavelength, and frequency of a wave.
• Does the medium in which a wave travels move with the wave? Why or why not?
• What is the relationship between frequency, wavelength, and wave speed?
• In what direction are the vibrations in a transverse wave, relative to the direction of wave travel?
• In what direction are the vibrations in a longitudinal wave, relative to the direction of wave travel?
• How does the speed of sound in water compare with the speed of sound in air?
• How does the speed of sound in steel compare with the speed of sound in air?
• Why doesn't sound travel in a vacuum?
• How are electromagnetic waves produced?
• List the frequencies of the electromagnetic spectrum in order from low to high frequencies.
• List the frequencies of the electromagnetic spectrum in order from short to long wavelengths.
• What is the principal difference between a radio wave and visible light?
• What is the fate of the energy in ultraviolet light incident on glass? Infrared light incident on glass? Visible light?
• What is the law of reflection?
• What is refraction?
• What is the angle between a light ray and its wave front?
• Which has the higher frequency: red light or blue light?
• Why is the sky blue?
• Why are sunsets red?
• Why are clouds white?