Unit 2 Electromagnetic Spectrum and Sound - 7th

Alex hears a loud rumble as he watches a space shuttle lift off from the launch pad. What medium does the sound wave travel through to get from the shuttle to Alex’s ears?

• air

• vacuum

• large vibrations

• energy

What is the name given to the lowest point of a wave?

• crest

• trough

• amplitude

• rest position

Kana shines a light onto paper. The light contains both blue and red wavelengths of light. If the paper were blue, what color (or colors) of light would bounce off the paper?

• only red

• only blue

• both red and blue

• neither red nor blue

Electromagnetic energy travels through space in waves. The electromagnetic spectrum includes all electromagnetic waves, arranged according to frequency and wavelength. Which of these is an example of an electromagnetic wave?

• radio wave

• sound wave

• ocean wave

• gravitational pull

The visible part of the electromagnetic spectrum consists of the colors that we see in a rainbow. Different colors correspond to different wavelengths of light. Which color of visible light has the shortest wavelength?

• red

• green

• violet

• yellow

Caleb counts the number of peaks that pass a given point in a certain amount of time on the beach. What property of waves does Caleb measure?

• speed

• frequency

• amplitude

• wavelength

Astronomers use radio waves to learn about the universe. Radio waves travel light-years through space before reaching Earth. Radio waves must be which type of wave?

• sound

• mechanical

• longitudinal

• electromagnetic

Electromagnetic radiation is energy that travels in waves. Some examples of electromagnetic radiation are visible light, radio waves, and x-rays. Which statement is true for all forms of electromagnetic radiation?

• All forms of electromagnetic radiation travel at the same speed in a vacuum.

• All forms of electromagnetic radiation have the same frequency.

• All forms of electromagnetic radiation have the same wavelength.

• All forms of electromagnetic radiation have the same amount of energy in a vacuum.

Which statement best explains why a banana is yellow?

• It emits yellow light.

• It reflects yellow light.

• It absorbs yellow light.

• It transmits yellow light.

Through which medium does a mechanical wave travel most quickly?

• solid

• liquid

• less dense gas

• very dense gas