Reflection of sound
Sound and light waves:
have similar wavelength
obey the laws of reflection
travel as longitudinal waves
travel through vacuum
The angle of reflection equals to the angle of incidence, only holds true for the light wave but not for a sound wave.
- Cinema halls
- Indoor stadiums
- Vacuum chamber
Propagation of sound waves follow the laws of reflection.
Depends on the medium
Depends on the source
If a person drops a pebble in a well of 100 m depth, after how much time (in seconds) will he be able to hear the sound?
Acceleration due to gravity, g=10 ms−2
Speed of sound in air, v=343 ms−1
For a sound wave, the reflected wave, incident wave and the normal to the reflecting surface always lie ___.
in different planes
in the same plane
in planes perpendicular to each other
incident and reflected waves are in the same plane while normal is in a perpendicular plane
What frequency do whales communicate at ?
Ultrasonic frequencies as high as 45 kHz
Infrasonic frequencies as low as 16 Hz
In the audible range of the human ear
Both A and B
- MRI scan
- no pressure
- high pressure
- high frequency
- low pressure