Sound Frequency and Period Calculation
What is the frequency of the sound produced by a cicada?
a) 128.6Hz
What is the period of the sound produced by a cicada?
b) 0.0078 second
Answer:
a) Frequency = 128.6Hz
b) Period = 0.0078 second
Frequency (f) is defined as the number of oscillation/vibration completed by a wave in one second. Mathematically, it is the ratio of the velocity of wave (v) to the wavelength (λ) of the wave. The formula for frequency is f = v/λ.
Given:
Velocity (v) = 346 m/s
Wavelength (λ) = 2.69 m
Substitute the values into the formula:
f = 346/2.69 = 128.6Hz
Period (T) is the time taken for a wave to complete an oscillation/vibration. Period is the reciprocal of the frequency. The formula for Period is T = 1/f. Given that frequency is 128.6Hz:
T = 1/128.6 = 0.0078 second
Therefore, the frequency of the sound produced by a cicada is 128.6Hz and the period is 0.0078 second.