Pitch is the sensation of certain frequencies to the ear. High frequency = high pitch, low frequency = low pitch.
f = c(speed of the wave) / <span>λ (wavelength)
1. 343m/s / 0.77955m = 439.99 Hz
This corresponds to pitch A
2. 343m/s / 0.52028m = 659.26 Hz
</span> This corresponds to pitch E
<span>
3. 343m/s / 0.65552m = 523.349 Hz
</span>This corresponds to pitch C
4. using f = c / λ
λ = c / f<span>
= 343m/s / 587.33 = 0.583999 m = 0.584 m
</span>
Echo sounding is a type of SONAR used to determine the depth of water by transmitting sound pulses into water. The time interval between emission and return of a pulse is recorded, which is used to determine the depth of water along with the speed of sound in water at the time.
A theorem can be proven (from axioms or prior theorems), using logic.
A hypothesis can be supported by evidence. The more evidence in support of the hypothesis, the more likely the hypothesis is to be correct. However, you’re always at the mercy of contrary evidence appearing in the future, to reduce the likelihood or even invalidate a hypothesis.
A (mathematical) proof suffers no such vulnerability to future evidence, as long as you hold the axioms of the theory to be true, and as long as there was no flaw in the construction of the proof.