temperature calculation
temperature calculation
(OP)
I recently took a standardized test that posed a theoretical question. What is the sum of 50 degC and 50 degF? I know its probably simple but (I'm ashamed to say) it stumped me. Would someone please set me straight. iwonder





RE: temperature calculation
<nbucska@pcperipherals.com>
RE: temperature calculation
But if the "sum" is intended to convey the concept of a temperature rise above another temperature (usually an ambient), then it is straight forward.
50F ambient + 50C*(9F/5C) rise =140F
50C ambient + 50F*(5C/9F) rise =77.8c
Note those two answers are NOT the same temperature... as it should be (they represent different temperatures).
One answer that would almost always be wrong (for any physical problem involving a temperature rise or delta-T) would be to convert temperatures between F and C using the formula that involves 32 and then add them. For example you convert the 50C rise to 50C*(9F/5C)+32=122F and then try to add this to 50F ambient and you get 172F... a meaningless number. 50C rise does NOT corresponde to 122F rise.... the 32F zeroing factor is irrelevant when converting temperature rises.
I think the final answer is that the question as you have posed it is irrelevant. More info regarding the physical problem is needed to determine what you mean by the "sum" of two temperatures.
RE: temperature calculation
RE: temperature calculation
Look posting above...
<nbucska@pcperipherals.com>
RE: temperature calculation
is that the complete question? or maybe its a mixture of two materials and find the total temperature?
for example...i don't think you can add the two like adding a series resistor...say i have a 100 deg.C of water in a cup and another 50 deg. of another water in another cup...say of equal volume...mixing them doesnt mean i have 150 deg of water!
and no matter how i try...i cant get any of the selections they gave you..
so my answer?...is e...none of the above..
interesting!
dydt
RE: temperature calculation
Not 150 bot 150/2 --- but you have to add.
<nbucska@pcperipherals.com>
RE: temperature calculation
This is not a simple question. I see it as a question to test your temp conversion knowledge and "best logic". The question may not have had a correct answer, but may be looking for the "best" or closest answer of the group, as many test questions did that I wrote taking engineering at University. The logical solution would have been to convert,
50C = 122F and 50F = 10C, so the combinations are,
122+50 =172F or 50C +10C = 60C,but 172F does not equal 60C and also these were not choices. If I convert the 4 possible answers to celcius, I get, 38.88,21,25,50. Since the answer definitely cannot be less than 50 C, by elimination I would pick 50C? Hope you passed!
Gary
RE: temperature calculation
RE: temperature calculation
For example if have a 50C rise above a 50F ambient the resulting temperature is NOT 50F +[50C*(9F/5C)+32F]=50F+122F=172F. It is 50F +[50C*(9F/5C)]=140F.
iwonder - I agree with dy/dt.... none of the above.