00:05A wavelength of 0.60 cm is produced in air and it travels at a speed of 300 m per
00:17second.
00:18It will be an audible wave, infrasonic wave, ultrasonic wave, none of the above.
00:32As wave velocity is find by using formula W is equal to lambda into F. So, to find the
00:43frequency this formula will become is F will be equal to V upon lambda. As V is obtained
00:54is 300 m per second, V is obtained is 300 m per second and wavelength is obtained is 0.6
01:10cm which
01:13will be equal to 0.6 into 10 raised to the power minus 2 meter. So, frequency will be obtained
01:23is by putting these values the speed of a wave is 300 m per second. So, 300 m per second
01:32divided
01:33by 0.6 into 10 raised to the power minus 2 meter. So, 300 divided by when we will take
01:46this decimal
01:47from left to right up to 1 digit, then we will subtract 1 from the power. So, this will become
01:576 into 10 raised to the power minus 3 meter. As the table of 6 on 6 is 1 times
02:06and on 300 is 50 times. So,
02:15frequency will be obtained is 50 into is here 10 raised to the power minus 3 is in the denominator.
02:26So,
02:26when we will take this in numerator, then it will become 10 raised to the power plus 3. 10 raised
02:33to the power 3 can be written as 50 into 1000. So, 50 into 1000 it will be
02:4450,000 hertz. As we know that men can detect waves from 20 hertz to 20,000 hertz. This is
03:06the
03:10audible range range of frequency which can be detected by human ear. So, here the frequency is obtained as 50
03:21,000 hertz. So, it is greater than 20,000 hertz.
03:39So, these are the ultrasonic waves because the frequency of ultrasonic waves is greater than 20,000 hertz. So, the
03:50correct option will be C ultrasonic waves.
03:56So, let us show that again,
03:59And we will just use the ultrasonic waves. So, we will ask for the ultrasonic waves. So, let us turn
03:59this over by
03:59then, let us turn this over by allowing thetez слово waves to 1 can be made. In thebay disconnected waves.
04:00So, let us try to take the sea
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