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We often use this logarithmic scale to describe the intensity of sound. Created by David SantoPietro.
Watch the next lesson: https://www.khanacademy.org/science/physics/mechanical-waves-and-sound/sound-topic/v/why-do-sounds-get-softer?utm_source=YT&utm_medium=Desc&utm_campaign=physics
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Sir,very nice explanation!
I am a bit curious since the formula is written out as :
10log(I/10^-12)
which is equivalent to
10log(I) + 120
Normally I would think that addition is simpler than division involving powers of 10, but maybe there's another reason.
In the example where the friends are yelling where I = 10^-5 W/m^2
You just take the -5 from the exponent, multiply by 10 and get -50 and add to 120 to get 70dB.
You don't have to do division by powers of 10 with negative exponents, even though it is easy once you learn it.
Brilliant explanantion.
You're joking right .
We brought the log to make the biiig number a small number.. Then again, why are we using the dB, the number is multiplied by 10 here.. Why not the B(Bel)????
Hands down, this is the best ever*10^100 definition of decibel I heard so far.
dam, #youcanlearnanything is true, but you can also, like me, go home and blow your nose and just about forget anything too. I already did that countless times in my life, ye. thanks
9:33 you forgot to the base 10 for the log but other than that a clear video
great really great
Why doesn't this have 1 billion views?
If the equation is for dB then why confuse it with B by saying Beta which can also mean Bell ?!
I actually didn't like the equations at first, I do now. If my math teachers were like this, I certainly would've loved math. I'll be studying mechanical engineering and really wanted to backout. But because of this, no. It's interesting.
I am 31 years old with BSc. in electronics engineering and 8+ years of experience in wireless communications and this is truly the most brief and beautiful explanation of decibels I have ever come across.
I wish I had this when I was in college. Now I am field engineer and I have to refer to the basics every now and then. I deal in optics mostly.
Shouldn’t it be Decabel if you multiply it by 10? Deci means 1/10th.
Such a friendly approach to explaining dB. Motivated teacher, funny and great analogies. Just a really, really well done explanation overall.
Great explanations! Thank you!
Is it just me or does he sound alot like chris from Mr Beast 😂……Amazing lecture…..you made it very interesting
If we’re thinking in terms of output, the dynamic range of an ADC is determined by the resolution. The lowest non-zero output value is 1, and the highest output value is (2N–1), where N is the number of bits in the generated digital word. Thus, a 14-bit ADC has a dynamic output range of (214–1) =16383. This could also be expressed as 84.3 dB or 14 stops. "How they get this 84.3dB? " how to solve this problem huhuhuhuh please help
This might be the first time ,I understood a concept in just a single watch
I love this video. Dang you are a great teacher. Finally, there is someone makes me like physics a little bit.
Thank you – highly informative and well presented 🙂
You are a god given teacher!! My god, i just learned some serious shit and refreshed 10 years of school in 5 minutes!!!!
thanks for concept …but u said decible scale where it is?
Logs can be used to scaling
Im freaking happy to find such nice people as you, and fucking mad at "the educational system". Greetings😀🍎
My professors are TERRIBLE at doing their job compared to you. They think their only purpose is spitting thousands of formulas without even trying to give us a sense of reality.
That was a great video!
I am in 7th class ans still understood it which is huge. You are the best teacher
Thank you Dr. Khan. Your competence is fresh air and your delivery superb. I finally clearly understand the dB scale.
Man… im a brazillian guy and i have a poor english, very basic… And you was capable of teach me about the fucking LOG and decibels
You are amazing… thanks
my ears after 2 years of pubg can forget about 1watt and germany for ever!
Log 10⁷ =8….. Isn't it????
Great teaching..funny too..😇
I love the nerd-like joking around and the brilliant explanation of how Log works, finally understood it, you're the man!
Wonderfully explained !! thank you !!
"10^7= 10^7" something i know as a kid(finally)
Very fun and simplified explanation! Very well done sir!
Also watch my video i'm a beginner creator at youtube…
4πr^2=area. Is the way to go . I think.
Thanks David Santopietro. Very good video. One word of encouragement. Try to be respectful of your viewers beliefs when tempted to use God's name as a flippant expletive. Thanks again. Bless you.
Awesome!
This formula is for sound intensity, but for measuring how loud a sound is at a specific point (e.g. our ear or a microphone) wouldn't we use the formula for Sound Pressure Level (SPL), which would be measured in Pascals instead of w/m^2? I would also love to hear an explanation of why in some contexts it's assumed +3dB is a doubling of volume but in other contexts people use +6dB? Still, this video is extremely well done.
This was dope, but what about negative decibles? I see that in my music recording software. Thanks!
I can't seem to find an inexpensive method for testing a ~150db car audio system. So far the devices require hundreds of dollars. Someone ought to invent a tiny microphone that plugs into a smartphone via 3.5 mm jack that reads up to 150 dbs and uses a particular db/spl app which tops out at 130db for the free trial version and jumps up to a higher db by upgrading to the Pro version of the app.. the microphone would need a price point of around $50. They'd sell like hotcakes IF it's accurate!
At the end example, shouldn't it be 7 decibels or 70 bels?
My brain is in fog now…i guess you are too smart for me
Thank you, Awesome. so easy explain. I finally understand the whole decibel thing so many years later kkkk
Would you please cut out the audio section of "in God's name" at 4:30?
…by far…thee best, clearest, simple well-defined explanation i have EVER encountered…i DEFINITELY got it……whew …finally …thank you SO much….!!