Transverse, longitudinal and sound waves

Grade 8 Science Worksheet - Challenge Me

Circle the best answer.

1. 1.

   Ari presses an ear to a long steel railing while a friend taps the far end. Two taps are heard: one through the steel, one through the air. Which comes first?

   • The tap through the air, as air is easy to push
   • The tap through the steel
   • The tap through the air, as it is louder
   • Both together: sound has one speed
2. 2.

   Sound travels about 1,480 m/s in fresh water and 343 m/s in 20 °C air. About how long does sound take to cross 3,000 m of lake water, Bo?

   • About 2 s
   • About 4,400 s
   • About 0.5 s
   • About 9 s
3. 3.

   Sound crosses 343 m of 20 °C air in about 1 s. Steel carries sound at about 5,900 to 6,000 m/s. About how long do 343 m of steel take, Esme?

   • About 17 s
   • About 0.6 s
   • About 0.06 s
   • About 1 s
4. 4.

   In 20 °C air, a 343 Hz note has a wavelength of 1 m. In water, sound goes about 1,480 m/s. About what is the note's wavelength in water, Kira?

   • 1 m
   • About 0.23 m
   • About 4.3 m
   • About 1,480 m
5. 5.

   Luz hears a sound pass from the water back into the air. What happens to its wavelength?

   • It gets longer, as air is easier to move through
   • It gets shorter, as sound slows down
   • It stays the same
   • It drops to zero
6. 6.

   Milo says sound in air must be a transverse wave, because books draw it as a wiggly line. Agree or disagree?

   • Disagree: sound is not a wave
   • Agree: the wiggle shows air moving up and down
   • Disagree: the air moves along the path
   • Agree: waves are transverse
7. 7.

   Noah says the sound from a speaker pushes the same air all the way across the room to your ear. Agree or disagree?

   • Disagree: the air stays; the energy travels
   • Agree: the air flows to your ear like a breeze
   • Disagree: sound needs no air
   • Agree: louder sounds carry more air along
8. 8.

   Pia says a wave on a rope carries the rope's fibers to the far end. Agree or disagree?

   • Disagree: a rope can't carry a wave
   • Disagree: the bits move in place
   • Agree: a bigger wave carries more rope
   • Agree: the fibers ride the wave to the end
9. 9.

   Ren chooses a model to show sound moving through air. Which model fits best?

   • A rope wiggling up and down
   • A single still dot
   • A spring with bunched and spread coils
   • Balls of air rolling from speaker to ear
10. 10.

    Tala chooses a model to show light from a lamp. Light is an electromagnetic wave. Which model fits best?

    • A spring standing still
    • Air particles carrying the light along
    • A wiggle across the direction of travel
    • Bunched and spread coils along the path