A student shakes a rope from side to side more forcefully. The rope's swing grows from 2 cm to 6 cm, but she still shakes it twice each second. What has changed about the wave?

Twelve wave crests pass a floating buoy in 4 seconds. What is the frequency of these water waves?

A student pushes and pulls the end of a stretched spring along its length. Bunched coils and spread-out coils travel down the spring. What kind of wave is this?

On a rope wave, one crest sits 60 cm from the next crest, and a trough lies halfway between them. What is the wavelength of this wave?

A water wave in a tank has a wavelength of 2 m and a frequency of 3 Hz. How fast does the wave travel across the tank?

Two waves cross the same water tank, so both travel at the same speed. Wave P has a shorter wavelength than wave Q. What must be true of wave P's frequency?

The amplitude of a wave is the distance from one crest to the next crest.

A duck floats on a pond while ripples pass beneath it. The duck bobs up and down but stays in nearly the same spot. What does this show about the ripples?

Sunlight passes through a clear glass window and makes a bright patch on the floor inside the room. Which behavior of light at the glass does this show?

A flashlight beam strikes a flat bathroom mirror in a dark room. The mirror absorbs most of the light that strikes it.

A black shirt and a white shirt hang in bright sunlight for an hour. The black shirt feels much hotter than the white one. What accounts for the difference?

A bathroom window of frosted glass keeps the room bright, but shapes behind the window look blurred. What is the frosted glass doing to the light?

A red apple sits on a table under ordinary white light and looks red. What is happening to the light at the apple's skin?

A music room's bare walls are covered with thick soft foam, and the echo that used to bounce around the room almost disappears. What is the foam doing to the sound waves?

Two identical cans of water, one shiny silver and one matte black, stood in sunlight for 20 minutes. Use the table. Which statement about the results is accurate?

A narrow beam of light meets a glass block, bends at the surface, and then continues on through the block. Which pair of behaviors does the beam show?

A ringing electric bell hangs inside a sealed glass jar. As a pump removes the air, the ringing fades until nothing can be heard, though the hammer is still moving. Why?

A girl tightens a guitar string, and the string then vibrates more times each second than before. What happens to the sound she hears when she plucks it?

A boy strikes a drum harder the second time. The drumhead moves further up and down, and the sound is louder. Which property of the sound wave increased?

A student presses her ear to a steel railway rail and hears an approaching train before any sound reaches her through the air. Why does the sound arrive sooner through the steel?

A boy shouts toward a cliff across a valley and hears the echo 2 seconds later. Sound travels at 340 m/s in the air that day. How far away is the cliff?

An astronaut on the Moon watches a rocket engine fire on a lander far across the airless surface. Sound from the engine travels through the empty space to the astronaut's ears.

A dog whistle produces a sound at 30,000 Hz. The dog turns its head, but the people standing beside it hear nothing at all. Why can the people not hear it?

A loudspeaker cone pushes forward and back, squeezing the air in front of it and then letting it spread out again. What are these squeezed and spread-out regions of air called?

A television remote sends a signal your eyes cannot see, using waves with wavelengths just longer than those of red light. Which region of the electromagnetic spectrum is this?

Visible light and radio waves from the same distant star both cross empty space to reach Earth. How do their speeds in that vacuum compare?

A detector at an observatory records gamma rays, X-rays, ultraviolet and visible light arriving from a distant object. Which of these four carries the most energy per wave?

An antenna on a rooftop receives microwaves, infrared, radio waves and ultraviolet from various sources. Which of these four has the longest wavelength?

A hospital scanner uses gamma rays and a car radio uses radio waves. Both gamma rays and radio waves belong to the electromagnetic spectrum.

Sunlight reaching a beach contains visible light, infrared and ultraviolet. Where does ultraviolet sit compared with the visible range?

A weather satellite sends its data to the ground using waves with a lower frequency than infrared but a higher frequency than radio waves. Which region of the spectrum is it using?

Sunlight crosses about 150 million kilometers of empty space to reach Earth, yet no sound from the Sun ever arrives. What does this show about electromagnetic waves?

A swimmer's shoulders are badly burned after an afternoon at the beach, even though the breeze kept the day feeling cool. Which radiation from sunlight caused the skin damage?

On a chest X-ray image, the bones appear pale and the softer tissue around them appears dark. What does this difference tell you about the X-rays?

An inspector points a thermal camera at a house on a cold night, and a bright patch appears over one poorly insulated wall. Which radiation is the camera detecting?

A song copied many times on analog tape picks up more hiss with every copy, while the same song copied as a digital file sounds identical every time. Why?

A car radio goes silent inside a long tunnel cut through rock and lined with concrete, then plays again once the car comes out. What is the tunnel doing to the radio waves?

A bowl of soup comes out of a microwave oven steaming hot, while the dry ceramic bowl holding it is still cool to the touch. How does the oven heat the soup?

A hospital seals surgical instruments inside plastic packets and passes them through a beam of gamma rays before the packets are opened. Why does this treatment work?

A fiber optic cable carries a phone call as pulses of light inside a thin glass strand, even where the cable curves. Which behavior of light keeps the pulses inside the strand?