Physics 9 Sound

Which of the following statement best describes frequency?

• the number of complete vibrations per second
• the maximum disturbance caused by a wave
• the distance between one crest of a wave and the next one
• the distance travelled by a wave per second

Which of the following vibrates when a musical note is produced by the cymbals in an orchestra?

• metal plates
• stretched strings
• stretched membranes
• air columns

If the speed of a wave is 340 m/s and its frequency is 1700 Hz, then lambda for this wave in cm will be :

• 20
• 2
• 0.2
• 200

A musical instrument is producing a continuous note. This note cannot be heard by a person having a normal hearing range. This note must then be passing through:

• vacuum
• water
• wax
• empty vessel

Which one of the following does not consist of transverse waves?

• musical notes of an orchestra
• light emitted by a CFL
• TV signals from a satellite
• ripples on the surface of a pond

Sound travels in air:

• if disturbance moves
• if particles of medium travel from one place to another
• if there is no moisture in the atmosphere
• if both, particles as well as disturbance move from one place to another

In the sound wave produced by a vibrating turning fork shown in the diagram, half the wavelength is represented by

• BD
• AB
• DE
• AE

The maximum speed of vibrations which produce audible sound will be in :

• ground glass
• dry air
• sea water
• human blood

The sound waves travel fastest :

• in solids
• in liquids
• in gases
• in vacuum

The speeds of sound in four different media are given below. Which of the following is the most likely speed in m/s with which the two under water whales in a sea talk to each other when separated by a large distance ?

• 1530
• 340
• 5170
• 1280