Relative Humidity and Dewpoint
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- Опубліковано 16 гру 2013
- In this video, we take a look at how to use the Earth Science Reference Tables and a sling psychrometer to calculate relative humidity and dew point.
Download the Humidity Reference Tables here: bit.ly/3QRoGsK
Download the Dew point Reference Tables here: bit.ly/3e3GFxF Additional science videos and resources at: science.glide.page
Subscribe to my channel: ua-cam.com/users/mikesamm...
My science teacher sent me this while we are quarantined and this was a big help and this helped me understand a lot me
same
here lmao
same
You win the internet with this video....thanks
This morning you open my mind and reinforce my knowledge .Thank you very much .
I appreciate for your explain and sharing knowledge .My instructor does not know how to explain this simple physic which is very important for the Air Conditioning trade and life sciences. May god bless you and your family .
yes the teaching method is crucial to the pupil's understanding.
I have the same problem with my geography teacher.
This was a huge help for me, you explained it so well I couldn't remember last time and kept getting these questions wrong😭
Something need comeing long not asking any thing olkhugefor selfed not playing today tackin stoping catr
thank you, i have my regents tomorrow and im trying to review as much as i can
I'll stick to my weather app
Helpful, thanks, jazaakallahu khairan.
Thanks u very much, I was looking for an explanation like this for many days. It helps me so much.
Thankkkkkkkk youuuu for making sense out of this. 5th video I found and answered the question.
This is very understandable to me. now I can properly define RH and Dew Point
Thank you for giving such a clear explanation. Very useful.
Thanks I got it now, you helped me a lot.
You have taught my ES class and you didnt even know it. Thanks!
Wow! Thank you very much for this explanation.
I could not leave without say THANK YOU. This concept was always a pain, now I feel an expert.
Thank you, this was very helpful!
thank you verry much it is so helpful
thank you vary much,it is so helpful
great explanation, thx a lot !!
THANK YOU!!!
50 years ago I worked for the US Forest Service in South Dakota. My day began and ended with the task of taking the weather and reporting it to the Weather Bureau. Not once did we ever do the dew point or did the Weather Bureau report the dew point, We recorded the low temp in the morning and the high in the evening with a special gauge When we did the humidity we wet the sock and then with a small hand fan we measured the humidity. When I went on tower duty I did the same thing but there was nothing that mentioned dew point, It was fun to go down off the tower and measure the humidity when the clouds were so low I couldn't see 5 feet in any direction I was the first lookout to report a tornado to the weather in the history of the Black Hills.
My only question is when did the weather bureau start recording dew point?
Based on your video, at what point does ESD - electric static discharge occur? Is there a way to accurately predict when static will occur and is there a chart for that? Thanks
Thanks man!
Dew point or relative humidity which one is a better indicator of comfort level & why? Thanks. You made it so simple to understand with the example.
Forgot how to do this, used to log in on the bridge in the Navy every hour/do the math. Thank you 🙏
Thanks, very helpful 😊
Excellent video!! Easy to follow; great for students! Well done.
I saw dew condensing on the furnace tubes inside the firebox during shutdown.
Could you explain the reason based on your knowledge of dew point?
I believe the pressure inside the firebox must have been higher or equal to the ambient pressure or the firebox or else would have buckled the fireb.
This is at sea level.
Why did the difference in the DBT become equal to the WBT inside the firebox? Did the DBT drop inside the firebox & decreased the difference with WBT equal to 0?
Thanks
Perfect explaination
Nice and easy explanation It´s helps me for my calculations. Thanks Mike.
No problem! Thanks for watching!
Is it Higher or lower heat transfer into evaporator when the difference in dry & wet bulb temperature increases, & the reason, could you please make me understand?
Thanks for this great value video.
Thanks a lot.
Next time consider pointing out what would happen at the dew point - moisture would start forming as a result of having reached your 100% humidity! (correct?)
thats very simple and eazy 2 understand
Thanks very informative!
Very helpful awesome video!
thanks
Very helpful.
very helpful to me.
Very much thanks...
Simply best,
Thanks
thanks very helpful
Very very interesting and understandable... Good job, great efforts to make the presentation simpler... Loved it...
Thanks!
Finding the depression? Ah should be pretty easy for me! 😅
Basic knowledge for a paint inspector
Thank you so much for uploading that
No problem!
Can somebody explain me this:if I know the temperature,RH and dew point in my living space,can that help me to predict potential risk from condensation and moisture on the walls?
Thanks man much easier to learn from you that from a NACE instructor
NATE*
exactly interesting presentation
「あなたのコンテンツはとても感動的です」、
I have a question, I have a cheap but accurate thermometer, I take note
of the temp, and stick wet cotton on the bulb, and swing it for a min,
then take the temp again.. I know it is supposed to be with 2 at the
same time maybe to be more accurate, but really the difference between
my reading when it is dry and doing the experiment is one min, in the
same spot, should that give me accuracy? when I do it, my room temp is
28, I swing it with wet cotton on the bulb for a min it comes to 26
only? does that mean I have 90 of humidity? we have 10% humidity
outside, so I placed wet towl near the AC to increase humidity but I do
not feel soggy at all.. where is the mistake? why it has to be 2
theremometer.
swung at the same time..? one thing though the bulb is protected with
little metal grid with 3 opening could that be the factor that give me
this mistake? thanks
If I didn't have a table available would there be some sort of formula I could use to calculate RH?
what
Could u please do one on enthalpy using similar tables ?
thanks alot u helped God bless u
Rabia afridi are u related to shahid afridi(cricket player)
can i ask what are the other methods aside from psychrometer?
nice video
If we say 40 percent RH, does it mean the mass of moisture per pound or partial pressure of vapor is 40 percent of the mass or partial pressure of moisture for 100 percent RH?
Could you please answer this for clear understanding?
Thanks again
Relative humidity tells you how much water vapor is in the air, in proportion to the maximum possible amount of water vapor, at that particular dry bulb temperature. For relative humidity, it makes no difference whether the number to quantify the amount of water vapor in the numerator and denominator, is mass based or mole based. For humidity ratio, it is convention to express it as mass based, kg water per kg dry air, unless otherwise indicated.
I'll give you an example:
At 6.9 Celsius, the maximum possible partial pressure of water vapor is 1 kPa, or about 1% of an atmosphere. This means 1% of the molecule population is water vapor. Since water vapor molecules are lighter than the average air molecule, this corresponds to a humidity ratio of 0.625 kg water / kg dry air.
So, if you had 40% relative humidity at this condition, it would correspond to 400 Pa of partial pressure, which would also be 0.25 kg water / kg dry air. In both cases, it is 40% of the maximum amount of water vapor in the air, however you opt to measure it.
Hi Sir Michael!How do I find the relative humidity and the dewpoint in which the dry-bulb is 35deg.C,the wet bulb is 28deg.C?The dry-bulb chart is only up to 30deg.C
I'd use Engineering Equation Solver (EES)
P1 = 100 [kPa]
T1 = 35 [C]
B1 = 28 [C]
W1= HumRat(AirH2O, T=T1, B=B1, P=P1)
R1 = RelHum(AirH2O, T=T1, B=B1, P=P1)
Results:
R1 = 59.2%
W = 0.0214 kg water/kg dry air
@@carultch thank you very much for replying
What is the equivalent dew point of 18 c in Fahrenheit?
cool
Thanks, but what about pressure and altitude? Can explain?
There’s so much more labor in dealing with the wet bulb which makes me think that there should be wet bulb charts instead and instead of calculating depression which nobody like they could instead going from wet to dry call it happy time difference calculation or HTDC for short.
I’ll wait for you to second this and bring it up for a vote at your next brainiacs convention
Would love a link to the charts
See page 12:
www.p12.nysed.gov/assessment/reftable/earthscience-rt/esrt2011-engr.pdf
Table name
Anybody else come here from their earth and sciences lab?
How to compute RH and DP without using the Chart?
There is a formula for the saturation curve, and for the adiabatic saturation lines, but it is complicated. It is based on the Antoine equation and the thermodynamics of gas mixtures.
If it were my choice, I'd use engineering equation solver (EES). It has built-in functions that do this behind the scenes. You call a function like r1 = RelHum(AirH2O, T=T1, B=B1, P=P1), where T1, B1, and P1 indicate the dry bulb temperature, wet bulb temperature, and pressure respectively.
Is that the theme song to Mr. Rogers playing in the background🤣
But why dew point is -8
thank you! background music is kind of annoying though
Look at the amount of comments
Bruh funny
This table isn't accurate, it's 1 degree out if you round up your figures (you have to round up because it only deals with whole numbers). Avoid using this and stick to the formulas.
Who is here for science lab
:-)
na nigga
Kay video h ye tre ko yhi nhi pta ki humidity ko find kse krte h.
Abe sale chutiya tu h kha s
gadho ko pda rhe ho
POV: you’re studying for middle school science lol
You interchange the word humidity vs relative humidity and they are not the same. By doing so you are confusing you audience. Not once in your example did yo calculate actual humidity only the relative humidity. As a point of interest you could have taught your audience how to calculate the base of clouds using dew point and standard lapse rates. You could have ended this on a wow moment.
i hate science
arbys
if the dry bulb temperature is over 30C, could you please provide more tables? Thank you.
You must love Jehovah your God with all your heart and with all your soul and with all your mind and with all your strength. You must love your neighbor as yourself. Jesus the anointed is Lord! Repent and be baptized and believe the Gospel.
Okay great explanation but you don’t sound British or European.
So what’s with using Celsius, is that your target audience?
Or is Celsius taken as the scientific viewpoint when kelvin I heard was the science go to for temperature calculations or such what.
I’ll be waiting for a long over explained dissertation on my question followed up with a documentary backed by the national weather service and broadcast at some scientific time that nobody will know when it’s on….🫤
Although I have it on good confidence that Europeans and Brit’s are quick to calculate from Fahrenheit to Celsius and vice versa but always ask for others to do it for them, of which I don’t understand why. Except that they want other to be as good as they are and start a competition for them to compete in and create a conspiracy as to why they don’t.
Thanks a lot man this was so understandable👍🏻👍🏻👍🏻👍🏻😊☺️😋
Thanks
exactly interesting presentation
Dew point or relative humidity which one is a better indicator of comfort level & why? Thanks. You made it so simple to understand with the example.
Relative humidity is an indicator of comfort.