Why does external pressure on a liquid increase vapor pressure]]>

Surprisingly different answers were given by online calculators. Though I am not a Physicist, please let me know the formula or principle...

How to calculate the calories burnt, during walking]]>

Temperature fluctuations in helium]]>

$$dS = dQ/T$$

Adiabatic Invsicid

$$dQ =0= dS$$

So no heat added or lost no change in entropy I'm fine with that...

Why is Bernoulli's Equation Isentropic]]>

Have you ever seen something just fall for no apparent reason? Its rather stable for some time and then suddenly it falls or moves? And you haven't touched anything. There is no wind. Nothing

What causes that?

It seems pretty strange, because...

Objects randomly moving]]>

I have got a question concerning the calculation of the overall energy input in random vehicle vibration tests.

I have got different power spectral density levels for different random vehicle vibration tests and would like to compare them with each other concerning the overall...

Overall energy input in random vehicle vibration tests]]>

Here is what I've heard so far:

- Refrigeration systems work based on using heat that is used merely to break attraction of molecules of liquids at their boiling point (eg, freon released through an expansion valve...

Cooling of an expanding gas]]>

Where W is the number of different distinguishable microscopic states of a system.

What I don't get is that if it's the position and velocity of a particle that describes a microstate doesn't it mean that W would be infinite...

Entropy question in classical physics]]>

How are physics theories discovered?]]>

Space station artificial gravity - how to spin up to speed?]]>

I’ve been trying to derive Posseuille’s Law and I’m very close. However there seems to be a small difference between my concluded formula and the real one but I don’t know why.

Here’s what I get:

Picture a cilindrical tube with a radius ##R## in which a fluid is flowing. From what I...

Deriving Posseuille's Law]]>

Voltage in series circuits]]>

I'm having some difficulty comprehending "normal" transmission of stress/strain through a solid body and "shock" transmission of stress/strain.

Imagine I have two bodies, one rigid - the other elastic.

If the rigid body is fixed in space, and the elastic body is flying at the...

Pressure wave vs. Shock wave in solid body]]>

The Normal Distribution - Random Errors]]>

Diffraction around objects]]>

excuse me if these happen to be basic questions, but I'm a psychologist/neuroscientist in training without any particular experience in physics, and I am just confronted with a very specific problem.

I need to measure the sound pressure experienced inside of an MRI scanner....

Estimating sound pressure (in an MRI scanner)]]>

My physics IB (international baccalaureat)]]>

One answer : talked about electro magnetic field being everywhere even...

Light through vaccuum?]]>

The two measured values are precise to two decimal points. But the first one has three significant figures, while the second one...

Significant Figures]]>

I was...

Does mass increase as velocity increases?]]>

What I don't understand is how's the object between the lenses is cloaked. Is it because the rays...

Invisibility cloaking using 4 lenses]]>

What causes alternator waveform shape?]]>

The object ,lets call it A,Its initally rest relative to us so it can be our inertial referance...

1N Force and going near the speed of light?]]>

Thoughts on Newton's Bucket and the relativity of rotation]]>

Assuming the process consists of two isobaric processes and two isothermal processes the work from B to C in terms of p

Thermodynamic Process]]>

When they are in space, past 100 km above the surface of earth where there is little air, when it's in the ballistic arc, past apogee does it slow down when it drops or speeds up due to gravitational acceleration without drag? I Am talking...

Question about suborbital flight and ballistic missiles]]>

here at (12:00-12:10) he says.The skater spins respect to space.

My question is How can space-time can be a referance frame itself ?

Is it means we can just pick a coordinate and make...

Can Spacetime be a Reference Frame?]]>

Progressive wave equation]]>

Deriving the progressive mechanical wave equation]]>

Light refraction in water]]>

I have 2 questions about the beam propagation of an Ti:sapphire-laser:

Picture 1: The cw argon ion laser brings the beam to mirror (1). Then...? Then the beam (100% of it), go to the birefringent plate (4), gets then reflectet to the first mirror again (1) , which reflects it to the...

Ti:sapphire: laser propagation]]>

Usually the equation for the ekman transport looks similiar to this (depends on the author)

[tex] u = V_0 e^{az} cos(\frac{\pi}{4}+az) [/tex]

[tex] v = V_0 e^{az}...

Ekman transport]]>

Starting with EM:

Naively, given the 4-potential ##A^{\mu}## has four...

Counting degrees of freedom in field theory]]>

I'd like to understand how filling my butane lighter works from a more rigorous point of view than just guessing.

How I can tell when my refill cannister is getting inefficient? (i.e. more rigorously than just shaking it or weighing it) I hope to detemine how...

refilling butane lighter the physics way]]>

Dropping glass on the floor]]>

Kleppner writes, "[t]he center of mass...

Center of Mass of Quarter-Circle Wire]]>

How many 400KB files will fit on 1mm^2 surface of hard drive]]>

Conservation of Information and indeterminism?]]>

General Question about Dissipation of Energy]]>

View attachment 111786

Thank you in advance.]]>

What is actually happening to a charge in a magnetic field?]]>

Or perhaps there is a basal level of kinetic energy of the molecules as they are vibrating?

Lastly, how can there still be flow if the pressure gradient is...

If KE is related to pressure on the wall for flowing liquid?]]>

Impact Velocity]]>

How does a physicist view mental phenomenons?]]>

How to do the Dark Frame Subtraction? (camera imaging)]]>

I have been doing some reading on "magnetic shielding" and have come across alloys such as MuMetal which have high permeability and so can block interaction between two magnets.

My question;

- Is this inhibition of interaction between the...

Inhibit repulsion between two like poles]]>

Boat hull speed]]>

I understand for the lift factor with the example of blowing air over the...

Faster velocity of water in tunnel Decrease in pressure?]]>

Electromagnetic effects, DC]]>

Current through Thin Wires]]>

For all intents and purposes, it appears as if a superconductor suspended above a magnetic field is defying gravity. I understand that there is no work being done (as...

Is there energy associated with flux pinning?]]>

Experimental investigation of c in electric & magnetic fields]]>

I remember hearing/reading somewhere that the energy transmission in a circuit like...

How does the Poynting vector factor into a normal circuit?]]>

Efficient Fast Orbital Transportation/Construction?]]>

...

Image formation in concave mirror]]>

Comment 2 says that resultant force is opposite the motion but I have some hesitations about it because let's think the situation that mass is moving back upward to its equilibrium...

The Sense of Restoring Force in Vibrations]]>

Question about Work]]>

The heat equation, change in concentration or temperature is equal to the average of its neighbors...

why is the wave equation different from the heat equation]]>

Why doesn't a charge repel a magnetic field in this example?]]>

Shorting of a capacitor]]>

So entropy is given by S= k ln W. where W is the number of microstates of a system. Know let's imagine there is a box containing a number of gas atoms let's say the gas atoms have a current position and velocity and say you can...

Microstates kT and entropy]]>

Why would a parallel circuit(or in blood) decrease resistance?

Here is my thought experiment and where I got stuck:

Say from aorta to one arteriole, the resistance is super high on that flow(this big amount of flow is entering a tinier area), but add more arterioles and we...

Why would a parallel circuit (or in blood) decrease resistance]]>

Cheers,

Glenn]]>

How many state changes per second could optical computing do]]>

Thank you]]>

Trust me I'm a Photographer -- I have a question]]>

black holes had such gravity as to have an

escapr velocity higher than c, which means that

things are pulled inwards at higher speeds than

the speed of light. Or am I overlooking something?]]>

Duration of sound in our brain (0.1s)]]>

First stop should be our very our PF Insights blog which hosts many physics tutorials...

Physics Learning Resources]]>

The Problem Statement

I have a jet entering leaving a nozzle at u

I am trying to equate the rate of momentum diffusement (or spread)...

Jet Spread Rate K Values- Momentum diffusement]]>

Is it true, that only

How would you pronounce ħ?]]>

universal stationary frame of reference for speed, d and t]]>

I understand that

Explaining the Hierarchy problem for beginners]]>

1. Papers

Recent Noteworthy Physics Papers]]>

Please critique the following logic...

When a runner hikes/runs to the top of a mountain, the chemical potential energy inside the muscles transferred into the potential energy of the runner's body mass at the higher elevation (Pe = mass*gravity*height = mgh). Energy is...

Energy transfer during uphill vs downhill running]]>

F_{B} = ρ_{DF} × g ×V_{DF}

Buoyant Force and what densities to consider?]]>

What are the missing ingredients? The answer is the boundary condition .With appropriate boundary conditions, zero divergence and zero curl will nail down a unique solution...

Zero divergence and zero curl]]>

https://en.m.wikipedia.org/wiki/Magnetic_field

Why is in the definition the way it is Generated?

When we had...

The right definition of magnetic field?]]>