### Physics - Wave Motion

#### Question - 1

IF frequency of tuning fork is 400Hz, find how far the sound travels when forks make 30 vibrations? Given velocity of sound in air is 320 m/s.

• A 32m
• B 30m
• C 24m
• D 34m

#### Question - 2

A steel wire has a length of 12.0m and a mass of 2.10 kg.What should be the tension in the wire, so that speed of transverse wave on the wire equals the speed of sound in dry air at 200C=343 m/s?

• A 2.56x104N
• B 3x106​​​​​​N
• C 3.4x105N
• D 2.06x104N

#### Question - 3

The velocity of sound in hydrogen is 1224m/s.Its velocity in mixture of hydrogen and oxygen containing 4 parts by volume of hydrogen 1 parts of oxygen is

• A 612m/s
• B 1224m/s
• C 2448m/s
• D 306m/s

#### Question - 4

The velocity of sound in air at NTP is 331m/s.Find its velocity, when temperature rises to 910C its pressure is doubled.

• A 372m/s
• B 382.1m/s
• C 423m/s
• D 392.5m/s

#### Question - 5

Tw3o copper wire of radius R1 and R2 are such that R1>R2.Then, which of the following is true?

• A Transverse wave travels faster in thinner wire
• B Transverse wave travels faster in thicker wire
• C Travels with same speed in both wires
• D Does not travel

#### Question - 6

A wire under tension vibrates with a fundamental frequency of 600Hz.If the length of the wire is doubled, then radius halved and the wire is made to vibrate under one-ninth of the tension.Then, fundamental frequency will be

• A 400Hz
• B 600Hz
• C 300Hz
• D 200Hz

#### Question - 7

Two sound waves are y1=Asin($\omega$t-kx) and y2=Acos($\omega$t-kx).The phase difference between the two waves is

• A $\pi$/2
• B $\pi$/4
• C $\pi$
• D 0

#### Question - 8

Find the amplitude of vibration of the particles through which a sound wave of intensity 2x10-6Wm-2 and frequency is 1 kHz is passing.Density of air=1.2kgm-3 and speed of sound in air =330m/s.

• A 1.8x10-4m
• B 1.6x10-8m
• C 2.4x10-8m
• D 1.6x10-2m

#### Question - 9

Two interfering waves of the same frequency have an intensity ratio frequency is 16:1.The ratio of intensities at the maxima and minima is

• A $25\over16$
• B 9
• C 4
• D $25\over9$

#### Question - 10

For stationary wave, $y=4sin({\pi\over15})cos(96\pi t)$ Find out the distance between a node and text antinodes.

• A 7.5cm
• B 15cm
• C 30cm
• D 22.5cm