When a guitar string is plucked, sound is produced by

• the size of the guitar

• the metal on the guitar

• the wood on the guitar

• the vibrations of the string

• 1

• 2

• 3

• 4

Tags

NGSS.MS-PS4-1

In her second demonstration, Jennifer observed that, as waves reached the towel, sand was left on the towel. What can she conclude about waves from this observation?

• Waves can move objects.

• Waves move in different directions.

• Waves cannot move smaller objects.

• Waves can be made by disturbing the surface of water.

Tags

NGSS.MS-PS4-2

Which of these could increase the amplitude of the waves in a calm pond? Choose all that apply.

• Rain hitting the surface of the water.

• An animal drinking water from the pond.

• 
  Ripples in the sand at the edge of the pond.

• 
  A person walking on a trail next to the pond.

• Rocks rolling down a slope and falling into the water.

Tags

NGSS.MS-PS4-1

When a guitar string is plucked, sound is produced by

• the size of the guitar.

• 
  the metal on the guitar.

• the wood on the guitar.

• 
  the vibrations of the string.

Tags

NGSS.MS-PS4-1

Leilani plays a knee drum.

When she strikes the drum with the mallet, it makes a sound. Why does the drum make a sound?

• because her knee moves

• 
  because the drum head is round

• because the top of the drum vibrates

• because the mallet is made of wood

Tags

NGSS.MS-PS3-5

Which points on the wave are the trough and the crest?

• Point W is a trough; Point Y is a crest.

• 
  Point Y is a trough; Point W is a crest.

• Point Y is a trough; Point X is a crest.

• Point W is a trough; Point Z is a crest.

Tags

NGSS.MS-PS4-1

A whistle produces a sound because blowing air in the whistle causes________.

• the whistle material to shake.

• 
  the air inside the whistle to vibrate.

• 
  the air to be absorbed by the whistle.

• the air in the whistle to heat up and expand.

When a book is dropped onto a wooden desk, the molecules in the wood begin to vibrate from the force of the book. Which of these is produced by the vibrations?

• friction

• interference

• sound waves

• ultrasonic waves

Tags

NGSS.MS-PS4-1

NGSS.MS-PS4-2

Which of these best describes frequency?

• the loudness of a sound

• the energy that bounces off an object

• the number of vibrations per unit time

• 
  the bending of light as it passes through substances