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Lots of questions on different subjects where you have to try to answer the latest question and if you are right then its your turn to ask the next question.

Moderators: playgirl, JUS, rodbox

#167017 by wildrover
Fri Jul 01, 2016 12:31 pm
If you buy oil for your car it will have a description such as 10w-40 on the can. What property of the oil are the numbers referring to?
#167898 by wildrover
Fri Nov 18, 2016 12:49 am
Well if no-one's got it after 4 months I suppose I'd better tell you that the answer is viscosity.

In 1800 the astronomer William Herschel conducted an experiment to show that light had a heating effect. He separated the colours into a spectrum using a prism and compared temperatures on a thermometer in the centre of the spectrum with a control thermometer placed next to the spectrum. He initially thought his equipment was faulty. What had he just discovered?
#167921 by Buzzie
Mon Nov 21, 2016 12:13 pm
Anything to do with IR and / or UV heat?
#167922 by wildrover
Mon Nov 21, 2016 2:46 pm
Yes - he was expecting to see the control thermometer lower than the thermometer in the middle of the spectrum but he placed the control thermometer as close as he could to the visible spectrum - right in the middle of the infrared spectrum so he got a bit of a shock when the control temperature was much higher than both the thermometer in the visible spectrum and the temperature in the rest of the room. A couple of experiments later he described infra-red radiation and was able to prove it was the band that carried most of the sun's energy..
#167924 by Buzzie
Mon Nov 21, 2016 4:01 pm
Where would you find the Cassini Division?
#168195 by Buzzie
Tue Jun 27, 2017 8:07 pm
You're corrrct though!
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