Sound(8th Grade > Physics ) Questions and Answers
Explanation:-
Answer: Option B. -> It converts ear drum vibrations into electrical impulses.:
B
The cochlea is a snail shell-like structure present in the inner ear that converts the vibrations of the ear drum or the tympanic membrane into electrical impulses. These electrical signals are then transmitted to the brain via the auditory nerve which then will aid us in hearing.
Explanation:-
Answer: Option A. -> 10 Hz:
A
Here, total number of oscillations = 10
Total time taken = 1s
Hence, time taken for 1 oscillation = 110 s
Thetime required to complete one oscillation is known as time period (T).
Now, frequency, f=1T = 10 Hz
Explanation:-
Answer: Option B. -> Enhance the vibrations reaching middle ear:
B
There are three bonespresent in the middle ear -malleus, incus and stapes. The function of these bones is to amplify the vibrations that reach the middle ear and send them to the inner ear.
Explanation:-
Answer: Option A. -> East-west:
A
In a longitudinal wave, particles of the medium vibrate parallel to the direction of wave propagation. As the given wave is travelling in the west direction, the particles will also vibrate along the east-west direction.
Explanation:-
Answer: Option D. -> The sound produced by the whistle has a higher pitch than the drum.:
D
The pitch of a sound depends on its frequency. It is given, the frequency of thedrum is lower than that of thewhistle. Hence, the drum produces a lower pitched sound as compared to thewhistle.