Answer:
Explanation:
Given
Frequency of whistle ![f_0=21\ kHz](https://tex.z-dn.net/?f=f_0%3D21%5C%20kHz)
Human hearing frequency ![f=20\ kHz](https://tex.z-dn.net/?f=f%3D20%5C%20kHz)
When a source or observer moves relative to each other then there is change in apparent frequency which is given by
![f'=f_0\frac{v-v_0}{v+v_s}](https://tex.z-dn.net/?f=f%27%3Df_0%5Cfrac%7Bv-v_0%7D%7Bv%2Bv_s%7D)
where v=velocity of sound(340 m/s )
=velocity of observer
=velocity of source
=apparent frequency
=original Frequency
![20=21\times \frac{340-v_0}{340}](https://tex.z-dn.net/?f=20%3D21%5Ctimes%20%5Cfrac%7B340-v_0%7D%7B340%7D)
![323.809=340-v](https://tex.z-dn.net/?f=323.809%3D340-v)
![v=16.19\ m/s\approx 16.2\ m/s](https://tex.z-dn.net/?f=v%3D16.19%5C%20m%2Fs%5Capprox%2016.2%5C%20m%2Fs)
Answer:
It reveals that light is a wave
Explanation:
Diffraction is the property of a wave in which there is a bending of the wave about the corners of an obstacle or aperture into the geometrical shadow of the obstacle or aperture.
This simply implies that a wave bends or spreads out when it passes through openings. Since the light diffracts through small slits and diffraction has been shown to occur in water waves and sound waves, this property of diffraction can only be characteristic of a wave and thus, this evidence reveals that light is a wave.
Answer:
6 rad/s
Explanation:
In a spring the angular frequency is calculated as follows:
![\omega=\sqrt{\frac{k}{m} }](https://tex.z-dn.net/?f=%5Comega%3D%5Csqrt%7B%5Cfrac%7Bk%7D%7Bm%7D%20%7D)
where
is the angular frequency,
is the mass of the object in this case
, and
is the constant of the spring.
To calculate the angular frequency, first we need to find the constant
which is calculated as follows:
![k=\frac{F}{x}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7BF%7D%7Bx%7D)
Where
is the force:
, and
is the distance from the equilibrium position:
.
Thus the spring constant:
![k=\frac{18N}{0.25m}](https://tex.z-dn.net/?f=k%3D%5Cfrac%7B18N%7D%7B0.25m%7D)
![k=72N/m](https://tex.z-dn.net/?f=k%3D72N%2Fm)
And now we do have everything necessary to calculate the angular frequency:
![\omega=\sqrt{\frac{k}{m} }=\sqrt{\frac{72N/m}{2kg} }=\sqrt{36}](https://tex.z-dn.net/?f=%5Comega%3D%5Csqrt%7B%5Cfrac%7Bk%7D%7Bm%7D%20%7D%3D%5Csqrt%7B%5Cfrac%7B72N%2Fm%7D%7B2kg%7D%20%7D%3D%5Csqrt%7B36%7D)
![\omega=6rad/s](https://tex.z-dn.net/?f=%5Comega%3D6rad%2Fs)
the angular frequency of the oscillation is 6 rad/s
Answer:
Soccer is a great way to maintain health, fitness, strength, and endurance. Soccer can help with cardiovascular health, lower body fat and improves muscle tone, increases muscle and bone strength, and improves health due to shifting between walking, running, and sprinting. Soccer can also promote teamwork and sharing, increase skills in concentration, persistence, and self-discipline, and can provide an opportunity to build your confidence and self-esteem, and it can also reduce anxiety.
Explanation:
6 degrees
4N
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