Recent content by rammer

Hi, I am looking for online molecular emission spectra database for spectroscopic analysis of plasma. It would be great if searching in it is based on a wavelength of spectral lines/bands. For atomic spectra I found this database: http://physics.nist.gov/PhysRefData/ASD/lines_form.html But I...

Anyone? I just need in what form/terms we express heat loss...

Hi, I have a device which is heated from inside by constant heat (let's say by Joule's heat - UIt). Some heat causes temperature rise of the device, some is lost into surroundings through device's surface. I measured how temperature of the device varies with time and I want to calculate...

thanks, that's exactly what i was looking for

Sorry, I meant grad f=F, and I want to get scalar function f from vector F (for instance electric potential from electric intensity).

What's the algorithm for finding scalar function satisfying div f=F if I know vector F?

big thanks to all of you

Hello, since I am very interested in universe, I would like to know something more about dark matter and energy. There are too few information on Wikipedia for instance. Could you recommend me any great book which can bring me some light about this stuff? I am 1st year engineering student (for...

As molar heat capacity I use "cv". Let's say an ideal gas is monoatomic, so "cv"=3/2 R. I involved equation pv=nRT as you suggested and figured something out: dU = dQ n*cv*dT=dQ ∫n*cv*dT=∫dQ n*cv*ΔT = Q ------ p*V = n*R*T dp*V + p*dV = n*R*dT (isobaric p. dV=0) ∫dp*V = ∫n*R*dT Δp*V = n*R*ΔT...

How to calculate heat transfer to an ideal gas during isochoric process? I only know initial and final pressures and volume. (Do I have to know whole cycle (closed loop)?) Here, no work is done so: dU = dQ n*c*dT=dQ But T and its change is unknown, so what would be the next step?

thank you

If we have a ball rolling down from inclined roof that has bottom part at certain height about the ground. I want to know where does the ball land after it leaves the roof. So at this point potential energy is transferred to kinetic (rotational + translational). My question is: What is the...

Thanks for both explanations :)

Suppose we have a spring placed vertically on a table. We put a body with mass "m" on it. The spring compresses by "x". Then sum of forces is zero, therefore: kx=mg, so k=mg/x But if we look on it as the energy problem, then: we hold the body on the string, then we release it, so loss of...

Yes, you're right, thanks. I finally got it correct. My mistake was I put the constant directly from initial conditions, not solving from integrated function.