## November 27, 2014

### Senior Inter Physics Important Questions for AP and Telangana States - Waves Chapter

The syllabus and examination pattern for Intermediate Physics (Senior
Inter) are same to AP and Telangana students. Here we are giving some
important questions for Waves chapter in Senior Intermediate in
English Medium

Q: Distinguish between Longitudinal Waves and Transverse Waves.
A: Longitudinal Waves :
1. In this wave, particles of the medium vibrate along the direction
of wave propagation.
2. Examples: Sound waves, Waves on springs.
3. When a Longitudinal wave travels through a medium compressions and
Rarefactions are formed alternatively.
4. Longitudinal waves are possible in solids, liquids and gases, as
they need bulk modulus of elasticity.
5. Longitudinal waves do not undergo polarisation.

Transverse Waves:
1. In this wave, particles of the medium vibrate perpendicular to the
direction of wave propagation.
2. Examples: Light waves, Waves on strings under tension.
3. When a Transverse wave travels through a medium crests and troughs
are formed alternatively.
4. Transverse waves are possible in solids only, as they need shear
modulus of elasticity.
5. Transverse waves can undergo polarisation.

Q: Explain the differences in the formation of Stationary Waves and Beats.
A:
Stationary Waves :
1. These waves are formed due to the superposition of two identical
progressive waves of same kind travelling
in the opposite directions along the same line.
2. Energy is not transported in the medium.

Beats:
1. These are formed due to the superposition of two sound waves of
slightly different frequencies travelling in the same direction.
2. Energy is transported in the medium. Redistribution of energy takes
place with respect to time.

Q: What is the ratio of the frequencies of harmonics in an air column
of same length in
(i) a closed pipe and (ii) an open pipe?

A: (i) In closed pipes, only odd harmonics are possible and the
frequencies ratio is 1 : 3 : 5 : 7 : ..
(ii) In open pipes, all harmonics are possible and frequencies of
harmonics are in the ratio 1 : 2 : 3 : 4 : ....

Q: What is Doppler effect? Write its limitation.

A: The apparent change in frequency of sound due to relative motion
between the listener and source of sound is called Doppler effect.
Doppler effect is applicable when the velocities of the source of
sound and listener are much less than the velocity of sound in the
surrounding medium.