A pipe of length 20 cm is closed at one end. Which harmonic mode of the pipe is resonantly excited by a 425 Hz sources. (Speed of sound in air .=340 m s -1)

Question

A pipe of length 20 cm is closed at one end. Which harmonic mode of the pipe is resonantly excited by a 425 Hz sources. (Speed of sound in air .=340 m s -1) (A) 1 (B) 3 (C) 5 (D) 7

Tardigrade Admin · Accepted Answer

((2 n+1) v/4 l)=v ((2 n+1) 340/4(0.2))=425 ⇒ (2 n+1)=(425 × 0.8/340)=1

Q. A pipe of length 20 cm is closed at one end. Which harmonic mode of the pipe is resonantly excited by a 425 Hz sources. (Speed of sound in air $= 340 m s^{- 1})$

1

3

5

7

$\frac{( 2 n + 1 ) v}{4 l} = v$
$\frac{( 2 n + 1 ) 340}{4 ( 0.2 )} = 425$
$\Rightarrow (2 n + 1) = \frac{425 \times 0.8}{340} = 1$

Q. A pipe of length 20 cm is closed at one end. Which harmonic mode of the pipe is resonantly excited by a 425 Hz sources. (Speed of sound in air =340ms−1)

1

3

5

7

4l(2n+1)v​=v 4(0.2)(2n+1)340​=425 ⇒(2n+1)=340425×0.8​=1

Q. A pipe of length 20 cm is closed at one end. Which harmonic mode of the pipe is resonantly excited by a 425 Hz sources. (Speed of sound in air $= 340 m s^{- 1})$

$\frac{( 2 n + 1 ) v}{4 l} = v$
$\frac{( 2 n + 1 ) 340}{4 ( 0.2 )} = 425$
$\Rightarrow (2 n + 1) = \frac{425 \times 0.8}{340} = 1$