Bernoulli's equation and window panes
Hi! I've been solving problems that apply Bernoulli's equations in *reasonable* situations. One comes from Serway's book. It applies the equation for the force exerted on a window pane in a stormy day....
View ArticleSemantics regarding current
I'm reading an introductory E&M textbook (with an electrochemical emphasis, so charge carriers are ions rather than electrons), and the wording my book uses to describe current is giving me a great...
View ArticleHit a roadblock trying to calculate minimal velocity.
Does anyone know how I can calculate the minimal initial velocity required to get to a certain altitude for a given object? I'm assuming an earthlike planet and a streamlined projectile with a maximum...
View ArticleKater's Pendulum Vs Bar Pendulum
I am not able to think which pendulum is more better. Both are compound pendulums and i think kater's is better, but for what reasons, i am not sure. Thank you in advance!
View ArticleWalter Lewin's riddle
http://www.youtube.com/watch?v=E185G_JBd7U At 37:00 he charges a conductor with a dielectric inside, removes the conductor plates and discharges them, and in the end puts them back into position. Then...
View ArticleVacuum chamber for filling bee comb
New here and very much out of my element being on ANY physics forum but here it goes anyway. I am a beekeeper in S. E. NC. I sell honey from my hives and donate the proceeds through my NC Non-Profit....
View ArticleCoulomb law dedution from Maxwell equations
I'm starting my study in eletromagnetism and I would like to know how do you deduce the eletric field produced by a single particle of charge q placed in the origin. The magnetic field is constant so...
View ArticleMotion of water bubbles at the surface of hot water
I've been thinking about this now and then, when boiling water. As the water becomes hotter the bubbles are rising in increasing numbers. The bubbles seem to either repel each other or merge to form...
View ArticleWhat would E field addition be if Gauss's law was different
What if Gauss' Law was div(E)=q2/eps0 Then if we had two point charges, how could we calculate the resultant E field at an arbitrarily point? Obviously superposition would not work anymore, so how...
View ArticleWhat is the reason for absolute zero temperature?
What is the empiric reason behind the assumption that there is lowest thermodynamic temperature (absolute zero)? And that all other temperatures of bodies in thermodynamic equilibrium are always higher...
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Trying to determine initial thrust on an object from angular velocity?
Hi all, I built an electric paper airplane launcher and I'm trying to figure out how much force or thrust is being applied to my paper airplane when it's launched. The setup looks like this: The discs...
View ArticleWhich thermodynamics concepts confuse or confused you the most?
I took a thermodynamics course last year and I know which topics confused me (fugacity for example) but I'm curious now in general about things people struggle with. Please add the time at which it...
View Articlefinding energy via integration
Hello, I havnt done physics in quite a while and I just want to ask a question about basic energy that i know how to deal with in algebraic terms, but not through means of calculus. I also don't really...
View ArticleAre newton's laws also an approximation?
So are newton's laws also an approximation to quantum phenomena. Can it be derived from quantum laws?
View ArticleHessian matrix of potential energy in electrostatic system
Hi everyone: I am rookie in classical physics and first-time PF user so please forgive me if I am making mistakes here. My current project needs some guidance from physics and I am describing the...
View ArticleDrip chamber pressure effect effect in fluid administration
Hi .. I am referring to a a typical IV set administratin of fluids. I am seeing reference in the literature mentioning that bottle height is from the fluid release level to the drip chamber in which...
View ArticleCauchy dispersion formula
Hi everybody, I would like to use the 'cauchy dispersion formula', ie (http://en.wikipedia.org/wiki/Cauchy's_equation): eta = A + B / w² Where : eta is the resulting IOR A is the base IOR B is the...
View ArticleDerivation of Gravitational Potential
Hi, The derivation of the Gravitational Potential formula, as I understand, is: [itex] W = Fd [/itex] (1) [itex] W = G \frac{M_1m_2}{r^2}d [/itex] (2) Substituting the Gravitational Force formula...
View ArticleHow to calculate force needed to push piston based on crankshaft value
How do you calculate the force needed to push against a piston based on the mass of the vehicle, the rpm of the crankshaft, radius of crankshaft (same distance as the center of the crankshaft to the...
View ArticleWave function in SHM
What is the wave function of a simple harmonic wave? y(x,t)=Asin(ωt+kx)
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