Usually, sound needs a medium to travel through, like a vacuum for example.
Light does not need a medium to travel, and since air is considered a medium, light is not dependent on that.
On the other hand, sound needs a medium to travel through, and outer space doesn't contain space, therefore, no sound.
Because the earth revolves around the sun and the whole earth isn’t always facing the sun it changes that’s why we have night and day and summer and winter etc
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:
Explanation:
Resistance of the tungsten wire
R = resistivity x length / cross sectional area
= 
= 107 x 10⁻⁴ ohm
Resistance at 120 degree can be obtained from the following formula


= 155.15 x 10⁻⁴ ohm
= 160 x 10⁻⁴ ohm ( rounding off to two syg fig )
current = 12.5
potential diff = 12.5 x 155.15 x 10⁻⁴ V
= 0 .1939 V
= .19 V
required electric field = potential diff / length of wire
= .1939 / 16 x 10⁻²
= 1.2 N / C
Answer:
The constriction causes the mercury column to break under tension, leaving a vacuum between the bottom of the column and that in the bulb, and the top of the column stays still at the position reached in the body - a "peak hold" system.