Answer:
697 m
Explanation:
From the question above,
Note: Alice hears the splash of the rock in the well through the help of echo.
Applying,
v = 2x/t........................ Equation 1
Where v = speed of sound, x = depth of the well, t = time.
make x the subject of the formula in equation 1
x = vt/2................... Equation 2.
Given: v = 340 m/s, t = 4.1 s
Substitute these values into equation 2
x = 340(4.1)/2
x = 697 m.
Answer:
The sound travels differently in different medium according the density of the medium.
Explanation:
The sound travels faster in dense medium and can be heard by the vibration of the bone present in the ear. The ear plugs reduce the sound intensity in both medium water and on land (air).
In air the sound is not heard properly due to the earplugs that stops the as the vibration are not able to produce as sound is not able to reach to middle ear, but Navy researchers have discovered that sound under water is heard by the bone present behind the ear, vibrations mastoid.
The wavelength emitted is indirectly proportional to the difference in the change in the energy level. For the wavelength 278 nm the change in energy level is significantly high. Further change in energy level is indicated by 454nm light but the difference in energy level for this wavelength to be emitted is not greater than the previous one. There is a possibility that these subsystems have now very low energy which should result in wavelengths ranging from 700 to 900 nm. There is another possibility that there is some metastable subsystems in the system which may cause LASER emission.
Answer:
The best option is for the following option m = 15 [g] and V = 5 [cm³]
Explanation:
We have that the density of a body is defined as the ratio of mass to volume.
where:
Ro = density = 3 [g/cm³]
Now we must determine the densities with each of the given values.
<u>For m = 7 [g] and V = 2.3 [cm³]</u>
![Ro=7/2.3\\Ro=3.04 [g/cm^{3} ]](https://tex.z-dn.net/?f=Ro%3D7%2F2.3%5C%5CRo%3D3.04%20%5Bg%2Fcm%5E%7B3%7D%20%5D)
<u>For m = 10 [g] and V = 7 [cm³]</u>
<u />![Ro=10/7\\Ro=1.42[g/cm^{3} ]\\](https://tex.z-dn.net/?f=Ro%3D10%2F7%5C%5CRo%3D1.42%5Bg%2Fcm%5E%7B3%7D%20%5D%5C%5C)
<u />
<u>For m = 15 [g] and V = 5 [cm³]</u>
<u />![Ro=15/5\\Ro=3[g/cm^{3} ]\\](https://tex.z-dn.net/?f=Ro%3D15%2F5%5C%5CRo%3D3%5Bg%2Fcm%5E%7B3%7D%20%5D%5C%5C)
<u />
<u>For m = 21 [g] and V = 8 [cm³]</u>
<u />![Ro=21/8\\Ro=2.625[g/cm^{3} ]\\](https://tex.z-dn.net/?f=Ro%3D21%2F8%5C%5CRo%3D2.625%5Bg%2Fcm%5E%7B3%7D%20%5D%5C%5C)
<u />
