Guess Paper Year 2011
CBSE Class IX
Subject: Physics
(Set-1)
1. Wave motion transfer
(a) momentum
(b) velocity
(c) energy
(d) mass
2. Speed of light wave is higher than the speed of sound in air by
(a) 1000000 times
(b) 100000000 times
(c) 10000000 times
(d) 300000 times
3. Sonic booms are caused by the combination of
(a) super sonic speed and pressure variation
(b) infrasonic speed and pressure variation
(c) ultrasonic sound and pressure variation
(d) pressure variation only
4. The term ultrasonic, supersonic &infrasonic mean
(a) decreasing frequency
(b) increasing frequency
(c) increasing loudness
(d) can not be related
5. Two audio devices of same brand differ in
(a) quality of sound
(b) reverberation
(c) frequency of sound created
(d) loudness
6. A pulse is
(a) a short term disturbance
(b) doesn’t repeat
(c) can travel
(d) all of these
7. Noise and music differ by
(a) quality
(b) ton
(c) note
(d) pitch
8. In longitudinal waves , the vibration of molecules will be
(a) perpendicular to the propagation
(b) parallel to the propagation
(c) depend upon the humidity
(c) none of these
10. Sound is produced when
(a) The prongs of the fork are vibrated
(b) Stretched rubber band is plucked
(c) Mechanical vibrations are produced
(d) All of these
Answer these questions below:
1. What is the difference between supersonic and ultrasonic?
2. Give two medicinal uses of ultrasound.
1. What is sonic boom?
2. Name two different forms of wave motion and express how they are created.
3. Name two physical quantities involved in the motion of sound in a medium.
4. Give two examples for the fact that mechanical vibrations produce sound
energy.
5. In a thunderstorm, does the light flash reach first or the sound? Why?