Question

A longitudinal wave is produced on a toy slinky. The wave travels at a speed of 30 cm/s and the frequency of the wave is 20 Hz. What is the minimum separation between the consecutive compressions of the slinky?

• A. $0.015m$
• B. $0.03m$
• C. $0.045m$
• D. $0.06m$

Answer 1

Answer: (A)

$0.015m$

The relationship between the frequency, wavelength and speed of sound or velocity is given as follows.
$Wavelength\lambda =\frac{wavevelocityv}{Frequency\nu }$

In the question, the velocity of sound is 30 cm/s, that is 0.3 m/s and frequency=20 Hz is given.
The distance between two consecutive compression is equal to the wavelength of the wave, therefore,
$Wavelength\lambda =\frac{v}{\nu }=\frac{0.3m/s}{20Hz}=0.015m$.
Hence, the wavelength of the sound wave is given as 0.015 m.