A source of sound of frequency 256 Hz is moving towards a wall with a velocity of 5m/s. Velocity of sound is 330 m/s. The number of beats heard by an observer standing behind the source is nearly -

Question

A source of sound of frequency 256 Hz is moving towards a wall with a velocity of 5m/s. Velocity of sound is 330 m/s. The number of beats heard by an observer standing behind the source is nearly - (A) (256 × 330/325)-256 (B) 256-(256 × 330/335) (C) (256 × 330/325)-(256 × 330/335) (D) (256 × 330/325)-(256 × 330/325)

Tardigrade Admin · Accepted Answer

<img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/581ac51597c3b28d43a16be4db50f163-.png" /> n D =256((330/330+5)) n R =256((330/330-5)) Δ n = n R - n D =(256 × 330/325) -(256 × 330/335)

Q. A source of sound of frequency $256 Hz$ is moving towards a wall with a velocity of 5m/s. Velocity of sound is $330$ m/s. The number of beats heard by an observer standing behind the source is nearly -

$\frac{256 \times 330}{325} - 256$

$256 - \frac{256 \times 330}{335}$

$\frac{256 \times 330}{325} - \frac{256 \times 330}{335}$

$\frac{256 \times 330}{325} - \frac{256 \times 330}{325}$

$n_{D} = 256 (\frac{330}{330 + 5})$
$n_{R} = 256 (\frac{330}{330 - 5})$
$Δ n = n_{R} - n_{D} = \frac{256 \times 330}{325}$
$- \frac{256 \times 330}{335}$

Q. A source of sound of frequency 256Hz is moving towards a wall with a velocity of 5m/s. Velocity of sound is 330 m/s. The number of beats heard by an observer standing behind the source is nearly -

325256×330​−256

256−335256×330​

325256×330​−335256×330​

325256×330​−325256×330​