Select the best definition for wavelength. the height of an oscillating electromagnetic wave the rate at which electromagnetic waves oscillate. the distance between two crests of an electromagnetic wave. the oscillations of electric and magnetic fields select the best definition for frequency. the oscillations of electric and magnetic fields. the height of an oscillating electromagnetic wave. the distance between two crests of an electromagnetic wave. the rate at which electromagnetic waves oscillate
Wavelength: the distance between two crests of an electromagnetic wave
Frequency: the rate at which electromagnetic waves oscillate
For a transverse wave (such as the electromagnetic waves), we can define the following quantities:
Wavelength: it corresponds to the distance between two consecutive crests (or between two consecutive troughs) of the wave
Frequency: the number of complete oscillations of the wave per unit time
Period: it is the time it takes for the wave to complete one oscillation - it is equal to the reciprocal of the frequency
Amplitude: it is the maximum displacement of the wave, measured with respect to its equilibrium position
Answer / Explanation:
Referencing the diagram of a resonance in a vertical tube as illustrated in the attached diagram below,
we can say that:
Vertical wave is the result of superposition of dual and identical waves.
We should also note that the only difference is that they travel in opposite directions to each other.
So, let assume a tuning fork is vibrated with frequency ν at the open end of the tube of varying length which can be changed during vibration with the help of water level change.
Also, let us assume the minimum length of the tube be L, when the resonance is heard.
Also, we assume that 1/4 of the wavelength λ of the standing wave is equal to length of the minimum length L of the tube.
Hence, we have:
λ = 4 L .
So, if speed of sound in air is V , then frequency of the tuning fork can be expressed as:
U = v / λ = v / 4L
Noting that we have been given the speed of sound in air as V = 343 m / s .
U = v / λ = v / 4L
343 m / s / 4 x 0.5525 m
= 155.20 Hz
Noting that 1 wave length in centimeter is 29979245800 Hz
Therefore, I wavelength in centimeter = 29979245800 Hz / 155.20 Hz
= 193 cm
Wavelength = 17cm
Frequency = 2017.65 s^(-1)
A) Standing wave is the result of superposition of two identical waves with only the difference being that they travel in opposite directions to each other.
Now, quarter wavelength transmission line, the number of quarter wavelengths in the length of the pipe is given as;
J = 2N - 1
Where N is the number of nodes in the air column.
Question says the 7th resonance is heard at that water level, thus, N = 7
So, J = 2(7) - 1 = 14 - 1 = 13
Now, J is also expressed as, L/(λ/4)
Where L is the water level and λ is the wavelength.
From the question, L = 55.25 cm
Thus, L/(λ/4) = 13
Let's make λ the subject ;
λ = 4L/13
λ = (4 x 55.25)/13
λ = 221/13
λ = 17cm
Now, frequency is found from the formula ;
f = V/λ
From the question, v = 343 m/s
λ = 17cm = 0.17m
Frequency = 343/0.17 = 2017.65 s^(-1)