D. A magnetic field created by the electric current causes the compass needle to move.
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.
calculate the power per hour of a radiator, knowing that it is connected to a common 110 v contact. and requires 20 Amp.
Answer:
2.2kWh
Explanation:
Given parameters:
Potential difference = 110v
Current = 20A
Unknown:
Power = ?
Solution:
To solve this problem, we use the expression below:
Power = IV
Power = 110 x 20 = 2200W
This is therefore 2.2kW
Power per hour = 2.2kWh
The answer is the last option
Explanation:
N2(g)<span> + 3H</span>2(g)<span> → 2NH</span><span>3(g) Is the answer. </span>
