Sound at 70 dB is 70 dB louder than the human reference level. That's 10⁷ times as much as the reference sound power.
Sound at 73 dB is 73 dB louder than the human reference level. That's 10⁷.³ or 2 x 10⁷ times as much as the reference sound power.
Sound at 80 dB is 80 dB louder than the human reference level. That's 10⁸ or 10 x 10⁷ times as much as the reference sound power.
Now we can adumup:
Intensity of all 3 sources = (10⁷) + (2 x 10⁷) + (10 x 10⁷)
Intensity = (13 x 10⁷) times the sound power reference intensity.
Intensity in dB = 10 log (13 x 10⁷) = 10 (7 + log(13)
Intensity = 70 + 10 log(13)
Intensity = 70 + 10 (1.114)
Intensity = 70 + 11.14
Intensity = <em>81.14 dB</em>
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Looking at the questioner's profile, I seriously wonder whether I'll ever get a comment in return from this creature, and how I'll ever find out if my solution is correct. For that matter, I'm also seriously questioning how and whether my solution will ever be used for anything.
Answer:
The object with the greater mass will have the greater momentum
Explanation:
The momentum of an object with mass <em>m</em>, moving with velocity <em>, </em>is given by the formula
M = <em>mv</em>
<em />
Since both objects have the same velocity <em>v, </em>it is clear that the object with the bigger mass will have the greater momentum
Refraction is simply the bending of light when it moves from one material into another. If light is beamed at 90° to a surface, no bending happens. But if you shine the light at an angle it will bend one way or another.
Diffraction is a process in which a beam of light travels through a gap or around a barrier, and spreads out as a result.
<span> Dispersion is the property that the speed of light in a transparent material is different for different wavelengths. Thus the index of refraction is likewise different.</span>
Answer:
,
(before collision),
(after collision).
Explanation:
The total momentum is obtained using the Principle of Momentum Conservation:

It is trivial to find that final speed and total momentum of the system are zero:

The total kinetic energy of the system becomes zero due to the inellastic collision and the same masses and speeds. Total kinetic energies before and after collision are, respectively:


D is the answer! Hope it helps