JEE Main 2022 · 28 Jun · Shift 1 · Physics Q50

PhysicsSingle correct+4 / -1Question 50 of 90

The velocity of sound in a gas, in which two wavelengths 4.08m and 4.16m produce 40 beats in 12s, will be :

282.8 ms

^{-1}

175.5 ms

^{-1}

353.6 ms

^{-1}

707.2 ms

^{-1}

Answer and worked solution

Official answer: D

Beat frequency. $\frac{40}{12}=\frac{10}3$ Hz.

Speed. $v\left(\dfrac1{4.08}-\dfrac1{4.16}\right)=\dfrac{10}3$ , so $v=\dfrac{10}3\cdot\dfrac{4.08\times4.16}{0.08}\approx707.2$ m s $^{-1}$ .

(D)

Topics:Beats

JEE Main 2022 · 28 Jun · Shift 1, Physics question 50