Light Interactions

Electromagnetic energy travels in waves. When we describe electromagnetic waves, we often talk about the wave’s length and frequency. Which of these statements accurately describes the relationship between the wavelength and frequency of an electromagnetic wave?

• If wavelength increases, frequency increases.
• If frequency decreases, wavelength increases.
• If frequency remains constant, wavelength increases.
• If wavelength remains constant, frequency increases.

Latif wakes up one morning and sees that it is foggy outside. Which term best describes the fog he sees?

• opaque
• reflective
• translucent
• transparent

If a material does not let any light go through, that material is called...

• transmitted
• translucent
• absorbent
• opaque

Heather puts a straw into a glass of water. She notices that the straw appears to be broken when she looks through the glass and the water from the side. Which term bestexplains why the straw looks like it is broken?

• absorption
• refraction
• scattering
• transmission

Calvin shines a thin beam of light onto a material, and the light refracts. Which diagram best shows what happens to the light?

• Picture # 1
• Picture # 2
• Picture # 3
• None of the Above

Habib looks around his classroom at different objects. Which object reflects almost all of the light that strikes it?

• a white poster board
• clear window class
• a red book cover
• black construction paper

During a thunderstorm, Sanjay saw lightning and then heard thunder 5 s later. Why does he see the lightning before he hears the thunder?

• He would have seen the lightning and heard the thunder at the same time.
• Sound travels faster than light.
• Light travels faster than sound.
• There is no reason.

Why does white clothing keep you cooler in the summer compared to black or dark clothing?

• Because the white wavelengths of light to not carry heat. 
• Because dark material reflects the hot waves away.
• Light waves carry energy.  A white surface reflects almost all the light and its energy.
• Black material does not absorb light waves.

Red light waves and yellow light waves travel through air and strike the surface of glass. Only the yellow light waves travel through the glass as shown in the figure below. Which of these phrases best describes what the glass does?

• reflects red light
• absorbs yellow light
• transmits yellow light
• transmits red light

A dolphin makes a noise underwater that is too high-pitched for humans to hear. What type of wave is this?

• water 
• electromagnetic
• mechanical
• microwave