Wavelength of two notes in air are (90175)mand(90173)m, respectively. Each of these notes produces 4 beats per second with a third note of a fixed frequency. Calculate the velocity of sound in air in m/s.
A
320
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
360
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
C
420
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
460
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is B 360 Given λ1=90175mandλ1=90173m If f1andf2 are the corresponding frequencies and v is the velocity of sound in air, we have v=f1λ1andv=f2λ2 f1=vλ1andf2=vλ2 Since, λ1<λ2 we must have f1>f2 If f is the frequency of the third note, then f1−f=4andf−f2=4 ⇒f1−f2=8orvλ1−vλ2=8 v[1759−17390]=8 v = 360m/s