Recent content by James125

I want to work out the heat capacity of the heater and thus the temperature that it will be.

Air is flowing through a pipe, through a heater matrix. Flow, Inlet temperature and heater power vary. Is it possible to calculate the heat capacity of the matrix by using the Inlet & outlet temperatures, power & flow? I'm assuming no heat loss to the pipe walls to make it easier, but I'm not...

Recently I have had a lot of eye strain from excessive computer use. The problem is because your eye lenses re stuck in a fixed position. I wanted to know if it would be possible to make a screen that is 1m away look like it is 4m away for example. Would it be possible by making the screen out...

I have a motorcycle battery which is 6Ah, with a maximum charging current of 0.6A/h. Is there a method of charging it whilst using a 2.7Adc (4A RMS) charger? I was thinking using resistors in parallel or series between the charger and the battery, but I am not sure exactly how.

Homework Statement I want to make a 555 circuit open and close some curtains. It has to open them at 6am and close them at 10pm Homework Equations N/A The Attempt at a Solution 555 circuits are not very accurate for long periods of time, so the solution is to use a plug in wall...

Is it possible to send enough light down a fibre optic cable to produce say 1000 Lumens? How would I go about calculating this? My thoughts here are using fibre optic cables to transfer light from the rooftops of buildings to the rooms inside. Is it possible? I know fibre optics are used to...

Pressure works out to be around 3000kg/mm2. I'm not sure if it's even possible to hold that in...Also I'm not sure if the gas inside would turn to liquid in which case it would certainly conduct the heat much more effectively, which would transfer to the case.

With increased pressure tungsten has a higher melting point. (source below page 30) 45kBar increases melting point from 3422oC to 3700oC. http://www.nist.gov/data/PDFfiles/jpcrd55.pdf An ideal 5800 K black-body, truncated would be 37% efficient...

I was thinking of installing a NTC thermistor, something like this; http://www.digikey.com/product-detail/en/SL22%200R712/570-1031-ND/749871

I want to be able to make my headlight bulbs last longer. I know the main reason they burn out is the massive current surge when you turn them on when cold. I was wondering if you put a thermistor in parallel, then the current would be split through the thermistor reducing the surge...

Stupid question really Urea is a solid. It's solubility in water is 107.9 g/100 ml @ 20 °C. Presumably 33% at -10C or something.

Hello all I am puzzled as to why SCR uses Adblue solution which is only 33% Urea. Why not use 100% Urea minimise fill ups and weight? Thanks

post #20 https://www.physicsforums.com/showthread.php?t=395212&page=2 I would have asked on that thread but it's closed

You can open the original file if you change the extension manually. Never to worry I have worked out how to save as xlsx. Missed out a factor of 2 first time round (forgot about it being 4 stroke). I still seem to be a factor of 1000 or so out. I have ~0.4w

I'm trying to calculate the power required from forced induction with this equation; W˙=m˙CpT1ηc⎡⎣(P2P1)(γ−1γ)−1⎤⎦ However I seem to be getting rather low results for work ~0.8W I have done my calculations in this spreadsheet. Any ideas where I've went wrong? thanks [SIZE="6"] Note...