Advertisements
Advertisements
प्रश्न
What is Galton’s whistle? To what use is it put?
Advertisements
उत्तर
A special whistle that can produce ultra sound, not heard by humans, is called Galton’s whistle.
It is used to train dogs because they can hear ultrasounds up to a frequency of 40000 hertz.
APPEARS IN
संबंधित प्रश्न
The sketches I to IV in following Figure show sound waves, all formed in the same time interval.
 |
 |
| I | II |
 |
 |
| III | IV |
Which diagram shows
- a note from a musical instrument
- a soft (or feeble) note,
- a bass (low frequency) note.
A microphone is connected to the Y-input of a C.R.O Three different sounds are made in turn in front of the microphone. Their traces (a), (b) and (c) produces on the screen are shown in following figure.
 |
 |
 |
| (a) | (b) | (c) |
- Which trace is due to the loudest sound? Give reason for your answer.
- Which trace is due for the sound with the lowest pitch? Explain your answer.
Complete the following sentences:
An average person can hear sound of frequencies in the range ______ to _________.
Name the sound of the frequency given below:
100 Hz
What is ultrasound?
Explain how do bats locate the obstacles and prey in their way.
What do you understand by the term ultrasonic vibrations?
The sonic boom of an aircraft has a time period of 0.00005s. Calculate the frequency of sound produced.
State the properties of ultrasound that make it useful.
The range of audible frequency for the human ear is
