Consider the three waves z1,z2 and z3 as
Z1 + Z2
Z2 + Z3
Z3 + Z1
Z1 + Z2 + Z3
A string is stretched between fixed points separated by 75 cm. It is observed to have resonant frequencies of 420 Hz 315 Hz. There are no other resonant frequencies between these two. Then the lowest resonant frequency for this string is
1,050 Hz
10.5 Hz
105 Hz
1.05 Hz
If a particle travelling with a speed of 0.9 of the speed of sound and is emitting radiations of frequency of 1 Khz and moving towards the observer, what is the apparent frequency ?
1.1 KHz
0.8 KHz
0.4 KHz
10 KHz
For a wave propagating in a medium, identify the property that is independent of the others
Velocity
Wavelengths
Frequency
All these depend on each other
The frequency of a simple harmonic wave is given by where x and y are in meter and time is in second. The period of the wave in second will be
0.04
0.01
1
5
A whistle producing sound waves of frequencies,9,500 Hz and above is approaching a stationary person with speed u ms-1. The velocity of sound in air is 300 ms-1.If the person can hear frequencies upto a maximum of 10,000 Hz, the maximum value of u upto which he can hear the whistle is
15 ms-1
30 ms-1
Energy not carried by which of the following wave ?
Stationary
Progressive
Transverse
Electromagnetic
The phenomenon by which stars recede from each other is explained by
Black hole theory
Neutron star theory
White dwarf
Red shift
Velocity of sound waves in air is 330 m/s. For a particular sound wave in air, path difference of 40 cm is equivalent to phase difference of 1.6π. The frequency of this wave is
165 Hz
150 Hz
660 Hz
330 Hz
The source of sound generating a frequency of 3 KHz reaches an observer with a speed of 0.5 times the velocity of sounds in air. The frequency heard by the observer is
1 KHz
2 KHz
4 KHz
6 Khz