View attachment 215250

This is the basic principle of an aeolipile.

You should be able to calculate the rotating velocity right? Knowing the mass and ignoring any resistance.

But then...

How to calculate rpm of an aeolipile]]>

So what is Rotational velocity? What does it define? How do signs work with rotation? What does its acceleration mean? Angular Velocity is...

What is Rotation]]>

I need some basic understanding between theory and practical with respect to blowers.

Blowers usually come with blower curves which give a relationship between Static Pressure and Flow. Usually, SP is inversely proportional to Flow, as in SP increases as flow decreases. Example of a...

Blower/Fan Curves]]>

Phase/group refractive index and reflection]]>

I'm investigating in using a dieletric barrier discharge for gas treatment, if I have two electrodes isolated by dieletric and the discharge gap between both of them has AIR..

how the ionization of air will take place, from where the source of electron which is going to start the...

Mechanism of discharge in DBD? (dieletric barrier discharge)]]>

This is a question related to an everyday activity .

View attachment 215253

My thinking - The base of the inclined plane is along the x axis and it makes an angle θ with positive x axis .We are looking from the +z axis .

There will be three forces acting on the person . Weight ,...

Walking up an inclined plane]]>

- Are there experiments that will demonstrate (a) there is an electric field present? Stark effect? (b) a magnetic field, (c) that they are...

Electromagnetic waves/radiation properties?]]>

If an ideal body of water is insulated and has a constant source of heating applied to it, can its temperature be expected to rise linearly?

(No. Even as I write this I see it

temp curve of heating water]]>

In thinking about vision, especially color vision, I understand that color as such is not a real property of the external world. Nor for that matter...

Why "light"?]]>

I'm firing alpha particles at a gold film, given that the plum pudding model is the pinnacle of human understanding of the atom, meaning I believe matter is made of...

Gold Foil Experiment]]>

Escape velocity and kinetic energy of the Earth]]>

Suppose there is a ramp with a height of 6 meters and length of 12 meters. A block of 5 kg is pushed up to the top of the ramp with a constant velocity. The force of friction is 15 N.

Here's the confusion:

By using the non-conservative force work energy...

Non-conservative work energy theorem and potential energy]]>

Time can be divided into smaller amounts of time.

So, 1 second can be divided into 1/2, 1/4, 1/6 etc seconds

SO, 1 second can be divided into 1 / infinite amount seconds

So, it follows that this will yield an infinitely small amount of time.

So, given that there is an...

How does time go forward?]]>

I have equation: View attachment 214965 and I need to find the value of parameter A at which the homoclinic bifurcation occurs.

I know, that in this case A=-0.34, but I solution, how to find it.

Can you help me, what numerical method I should use to find A?...

Critical value of homoclinic bifurcation]]>

In an even very simple geometry we see a constriction or rather offset of the Proton flux at surfaces (surface 1118,...

MCNPX Mesh Tally Problem: Offset of proton flux at surfaces]]>

But, suppose the Earth were 10 times bigger.

Would it be possible for everything on Earth to scale with this increase - Earth systems, land masses, trees etc (but also remain unchanged to us (except everything everything would be bigger)....

Scale factor question]]>

Question about speed and vehicles]]>

https://www.wired.com/story/how-to-hoist-yourself-out-of-a-hole-with-physics/

Remember folks: Don’t try this at home as you may be late for dinner.]]>

Coalesced drops form a bigger drop and there is extra energy spare.Now this energy is said to give kinetic energy to bigger drop.Which factor decides the velocity of coalesced drop?

Is it just any accidental push after coalescence?

I think also that the process is just feasible...

Coalescence of drops]]>

Magnetic Energy = 1/2LI^2?]]>

This YouTube video shows various shapes of pyrolytic graphite suspended on an alternating polarity matrix of square neodymium magnets.

View attachment 215195

As I understand the principle of diamagnetic anisotropy, the stronger the external...

Diamagnetism & levitation of pyrolytic graphite explanation]]>

I have a problem here. I dont get why the stagnation pressure equal the height of the water in the pitot tube.

The liquid manometer is easy. We analyse the forces on the horizontal contact surface of the tube and the liquid manometer so P1 = Density * g * h...

Pitot tube]]>

Please tell me if I should provide more information, i'm pretty new to this.]]>

How does vibration affect the Higgs field interaction?]]>

In this book I found by chance on Google, the author claims that “solutions of the wave equation only take the form of functions (...) in one and three dimensions. In two dimensions solutions are more complex”. Then, at the end of the paragraph of interest...

Is this book correct regarding waves in even dimensions?]]>

This may be an incredibly simple question, but I am looking for some help to clarify things for me.

I am a researcher interested in animal locomotion. Currently, I am working on a project collecting single limb force data (vertical, horizontal, and mediolateral substrate reaction force...

Predicting the vertical/horizontal/mediolateral force of a lungfish limb]]>

If there is a difference of electric potential between two points in space, since electric potential is electric potential energy per charge, there is a difference in the electric...

What about the electric field in a circuit with resistors?]]>

As a crude analogy, when wind blows in the face of a windmill, we can intuitively see why it rotates clockwise or counterclockwise. It is because of the...

Why do electrons obey Fleming's left hand rule?]]>

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

Physics Learning Resources]]>

How can X-ray energy transitions be identified?]]>

I have been doing an experiment at school looking into how the angle of a cone affects the time it takes for it to fall 2m. The data consistently shows an inverse relationship but it is unclear whether or not they are inversely proportional i.e. if the angle doubles, the time taken to fall...

Investigating Drag with Paper Cones]]>

Having Trouble Finding G-Force of an Impact -- Details in post]]>

Output of a half wave rectifier]]>

Self-Induced Emf and Angular Frequency]]>

Please, I learned that a wave is something the photons "surf" on, like, in one electromagnetic wave, can have many photons.

So, is this true? Like, I though that one gamma ray and an infrared photon would ride different waves...

More: the light from the...

The relation between photons and waves]]>

Now I was wondering how this formula could be applied to continuous matter. Let us imagine a very simple case where we...

Gravitational potential energy and continuous matter]]>

Why do neutron stars have such powerful magnetic fields?]]>

Quantifying Static Electricity Hazard with High Explosives]]>

I'm trying to get a conceptual understanding of why switching gears makes pedaling easier or harder. I think I understand what's happening with the

Let's suppose our...

Bicycle gears, force, torque]]>

Fusion power, still the king of power?]]>

Sorry for my English...

I have made some calculations. By Iterative calculation. With Excel.

The time that need two objects to fall from 10 meters to 2 meters.

The mass of the objects i choose are:

1 and 10 kilos.

2 and 10 kilos

5 and 10 kilos.

And.

1 and 9 kilos

3 and 7 kilos.

5 and 5...

Duration of a fall]]>

Dimension of human perception]]>

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]]>

My job is to perform a stress analysis to determine the regions of maximum...

How can I draw a free body diagram of a rotating wheel?]]>

Real objective time clock/s?]]>

I want to get quantitive value about that problem.

What would be the kind of wave or EM field that could heat human tissu of 1°C in (say a body part like the thigh), say in one hour, at a distance of 2m ?

We could...

Energy of beamed EM field that can heat human tissue]]>

To illustrate the...

How do I name a generalisation of the wave equation?]]>

Can there be a subquantum level?]]>

Basic question on atomic forces]]>

what will be the time period of oscillations??]]>

In 1815, Fresnel made, with Arago, the experience of Poisson spot. (or

Light experience.]]>

Now if i do (15.58eV / 2.6eV) it equals ~6 photons.

Now to figure out how many Joules are required for 1 photon I do

(6.626*10^-34S *...

Calculating how many Joules are required to make a photon]]>

Apparently a long TE gives a good T2 image yet how is TE length selected?

If I stand in a cave and shout I don’t control the time that the echo gets back to me, right?

Cheers

Ian]]>

will the torque for this force = 0

explain according to the torque relation]]>

I know that L = Ke - Pe

I also know the equation d/dt(∂L/∂x’) - ∂L/∂x = 0

1.) Apparentaly solving this equation gives the equations of motion. What exactly does that mean though? I solved a very simple problem and got the...

Lagrangian Mechanics]]>

https://www.nasa.gov/mission_pages/mars/news/mars-20070315.html

Some points to note are

* The polar region contains enough frozen water to cover the whole planet in a liquid layer approximately 11 meters (36 feet) deep.

* The radar sees through icy layers to...

Fill Mars with water]]>

I have always wondered about photons and how they interact with the world. If I...

Photon Detection]]>

I have been looking at physics calculators, but cannot seem to find precisely what I need. I don't need a very precise answer, merely a realistic ballpark one.

I need to know how we find the rough speed of an object's movement when a certain amount of force is applied to it.

For...

Force (in lbs) to speed?]]>

http://edition.cnn.com/2015/03/05/tech/balloons-fly-edge-of-space/index.html

look at above link.

balloons goes just 36 km above earth surface. but earth orbit is 100 km away.

so my thinking is if we pump oxygen outside near helium balloon...

Space Travel with balloon assist]]>

velocity=sqrt((-g)(horizontal distance)/sin(2theta))

sorry, symbols is not working on me laptop at the moment

Its been a...

what equation is this?]]>

When do I apply this equation of Wother=E2-E2? I get confused cause I thought frictionless meant that energy is conserved. View attachment 214748]]>

Does attenuation affect subsequent interference?]]>

From my knowledge, Internal forces does not change the total mechanical energy while external does.

But than why is gravity an internal force while normal force is external?

Is there any other ways of...

Stupid question of forces from one who skipped Physics B]]>

How can this interesting set of mirrors be constructed?]]>

Laser Crystals -- effects of crystal size]]>

For complete combustion of most hydrocarbons (blue...

Processes that determine the color of fire]]>

Computer engineering projects for physics. Proposals?]]>

Laser Question - Axial Modes & Gain Saturation]]>

Blocks sliding down different lengths of ramp]]>

Charge Carriers in the Hall Effect]]>

I found that superconductors have zero resistance but are too expensive. So ceramic can be used, but that is brittle....

Is it possible to use technology from a nervous system?]]>

I've got a percentage error for x and know how to deal with it for trig functions and powers, however since both errors are from the same source:

y = sin(x)^2 / x^2

Should I just...

Error Propagation (Percentage) - sin(x)^2 / x^2]]>

I tried using the Bernoulli equation to solve this. I took two points at the surface of the water in both the containers and formed this equation:

[tex]gh_{b}=\frac{1}{2}v^2+gh[/tex]

This is assuming that the velocity of the water in the large tank is approximately...

Modelling water tanks]]>

Stress strain curve]]>

I know that mechanical energy is considered as a sum of potential and kinetic energy. But I still do not understand exactly what is the mechanical energy.Whether kinetic energy and potential energy are forms of mechanical energy or that the kinetic and...

What exactly is mechanical energy?]]>

##(\textbf{F},\textbf{G}) = \int \textbf{F}^{*}\cdot \textbf{G} \thinspace d^3\textbf{r}##

And that if ##\textbf{F}## is...

Define inner product of vector fields EM]]>

WILL HE?SHE STAY AFLOAT OR WILL HE?SHE CRASH INTO THE GROUND?

What acceleration will he/she hit the ground?]]>

On a similar note, if you wound a wire around a sphere in...

Forces on magnets in a uniform magnetic field]]>

h(x,t) = \Delta H .erfc( \frac{x}{2 \sqrt[]{vt} } )

$$

where x is distance, v is diffusivity (material property) and t...

Modeling analytical solution of 1D heat equation]]>

and in CGS units:

$$\mu_B=\frac{e\hbar}{2m_ec}$$

So the dimension of the electric charge in SI, ##[q_{SI}]##, is related to the dimension of the electric charge in CGS, ##[q_{CGS}]##, by:...

Dimension of the electric charge in CGS and in SI?]]>

I have a 300 cubic foot tank of nitrogen air that will provide nitrogen to a rectangular pipe at 5 psi with a flow rate of 10 CFM to atmosphere at the...

Compressed Nitrogen]]>

I'm wondering how, for each peak in an x-ray spectra from a material (and using a crystal analyser), it is determined which energy level jump the peak corresponds to?

How would you figure out the correct value of n to substitute into Bragg's Law to find the energy of the beam?

Thank you!]]>

Suspending a Magnet or Ferrous rod in a Tube]]>

Magnetic materials]]>

Is circulation just the work done as you go around a circle once?]]>

View attachment 214393

The picture above shows the piece of ice that was put in the...

Why are only some parts of this ice block cloudy?]]>