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OK guys (gals?),
Please feel free to laugh at me for this one, it is late, my brain is mush and I can't find my trusted rule of thumb book... :mad:
What will the temperature rise be in 1m2 of air if 1 watt of heat is added to it for 1 hour?
(Assuming no losses or other heat transfers occur and that we start with dry air at 20ºC)
I will now go and collect my free bus pass, get my slippers on and complain about the youth of today.
Assuming you mean 1m3
Straight forward Viking..
1 Watt = 1j/s
1 hour = 3600 secs
so 1 Watt for 1 hour = 3600joules or 3.6kj
The mass of dry air at 20c is 1.205kg
Specific heat of air is 1.22kj/kg, so
Using the heat transfer formula Q = mass x c x (t1-t2) we can transpose to find the dt
3.6/(1x1.205)/1.22 = dt
dt = 2.4488K
Temperature rise = 2.45 degrees C
Typo I think frank!
3600joules = 3.6 Kj (not kw)
Thanks Frank,
You are of course right m3 it is.
And thank you for the formula.
:cool:
Spot on MF...wine kicked in lolQuote:
Originally Posted by mad fridgie
I'll have to recalculate tomorrow... Beds calling☺
Correction made ☺
Cheers Frank,
You are a true gentleman.
:cool:
You need to retune to vine from beer!;)Quote:
Originally Posted by frank
I telling this from personal expirience!:)