Recent content by math_04

The velocity should be 0 m/s at pipe wall right? Because of the no slip condition?

Homework Statement Water at 20 degrees C flows in a 0.8cm diameter pipe with a velocity distribution of u(r) = 5[1-r2/(16x10-6)]m/s. Calculate the shear stress on (a) pipe wall (b) at a radius where r = 0.2 cm (c) at centerline of pipe Homework Equations Shear stress = viscosity x du/dr...

Thanks for the article meopemuk! It was an interesting read although I have a couple of questions. 1. In the section on special relativity, you write that the Lorentz transformations are derived for 'photonic events only'. I only thought that people used photonic events to talk about time...

Hi, I am wondering what everyone here thinks about some of the work that has gone into researching quantum mechanics without spacetime. I am only a third year physics student at college (having done classical mechanics, electromagnetism and quantum mechanics upto perturbation theory, special...

Yes, well Obama has not faced the criticism that Bush faced! Well at least they are frightened of Obama, that has got to be a good thing :smile:

It is a safe bet. Iran, despite its statements about Muslim brotherhood and leading the Muslim world against 'aggression by the West, puts its national aspirations first. It has precious few allies in the region, and as a military power and a nation with veto powers in the Security Council...

Homework Statement Check the gradient theorem for the scalar field T= x^2 + 4xy + 2yz^3 and the paths a) (0,0,0) to (1,0,0) to (1,1,0) to (1,1,1) Homework Equations Equations = none well maybe divergence of a vector field= (df/dx)*x + (df/dy)*y + (df/dz)* z where x,y and z are...

Looks like Obama has few friends in Russia! http://www.washingtonpost.com/wp-dyn/content/article/2009/07/07/AR2009070702321.html Obama was probably right when he said that Putin has one foot in the old Cold War style days. Some Russians seem to view the US as a foe, lessening that distrust...

Photovoltaics engineering maybe? Depends on your college and what they offer. I believe that photovoltaics (solar panels) is a branch of electrical engineering, it is where I study. A physics degree would also serve you well, but you probably will need to study postgraduate as well.

Here is a transcript of President Obama's speech in Moscow http://www.google.com/hostednews/ap/article/ALeqM5hEgzmDPlmhHVfmc1U9rZXLmsQiuwD999J9Q00 Interesting speech and pretty similar in style to the one given in Cairo. He praises Russia on many occasions,does not focus too much on...

You think so? .

An individual who realizes the boundaries of his knowledge would be in a better position to push those boundaries of knowledge further and lessen his ignorance on a particular subject(s). Like Harry Callahan (Dirty Harry) once said 'A man must know his limitations'. :smile: I think realizing...

They are sought after, remember that physicists are hired across many fields like defence, technology, energy, teaching etc. Normally a bachelor's degree will take you to teaching in schools, working at a technological firm etc. If you aim for a Masters or PhD, you probably will be able to...

The Chinese government does not torture dissidents because they are religious. They torture because the dissidents represent a threat to the ruling government. Purely political and not religious.

Sometimes, I think we use the 'freedom to practice religion' sentence a bit too much. It really depends on the situation. If you are going to teach a child in school about intelligent design and creationism with a strong emphasis that what is been taught is true, then it is wrong. If you take a...