so here's what i wanted to check, to make sure I haven't missed anything obvious

vertical lift achieved by using vertical repelling fields

rotational motion is...

magnetic levitation with permanent magnets]]>

View attachment 207515

http://imgur.com/a/fquuF

View attachment 207516

In the first image, first line in the last paragraph.

If I understood it correctly, the coefficient of attenuation for a single optical fiber, is alpha = (10/L)*log(P(0)/P(L)). Assuming if I knew the properties of the optical fiber and the amount of optical fiber in the bundle, then the total attenuation for the bundle is approximately number...

How to calculate attenuation for optical fiber bundle?]]>

I may have this completely misunderstood, so bear with me and correct me where I'm wrong please.

There are 2 types of currents, DC and AC. Correct?

AC stands for Alternating Current and DC stands for Direct...

Can any physical quantity be vectorless?]]>

What equation would allow one to predict the proportionate time decay of such...

Expected time decay of a sound based on its relative volume?]]>

Predicting lift on an Aerofoil with varying Angles of Attack]]>

Sine Wave Frequency Bandwith]]>

Ever since I can remember, I've been taught that when light crosses the boundary between two mediums with different refractive indices, its trajectory changes due to a reduction or increase in its speed. I've never given this a second thought, but today I...

Why doeslight "turn" when it travels through water?]]>

How much space does a single photon occupy?]]>

Comparison of tidal forces acting on the Moon vs Enceladus]]>

Do quantum fluctuations mean metric fluctuations?]]>

Air movement in an exhaust systems]]>

Energy perspective on deterministic intelligence]]>

A Question about Diffraction...]]>

I was wondering if the power profile of a single mode waveguide can be changed? I mean, a wave that travels through the waveguide will have a harmonic shape, right? Is it possible to get a different shape of the power profile?

Thank you :)]]>

potentiometer nulling voltages in a circuit]]>

If I were to cut the string and let the board move, I know I would get rotation. But, since the center of mass of the beam is moving as well (in a circle) could I also say that the board is translating once the string is cut?]]>

Is it possible that an electron can have a negative mass?]]>

Compressing a bottle with water - initial velocity of water]]>

View attachment 207402

if yes , what shape of prism should i use to do this?

Thank you]]>

Levitating a metal ball]]>

it said that delta S>=0

in an isolated system. i know why they put " = " sign, but i don't know why it is still possible that dS>0 in an isolated system

because in an isolated system,it is said that dQ=0 (because no heat transfer between the system and the...

Why there is a " > " sign in the entropy in isolated system]]>

dependence of index of refraction on frequency]]>

What is then initial velocity cause when t=0 both object dropping and moving upwards had 0 velocity - in other words when object came to motion at both places it had some velocity?]]>

I understand brake locking as the situation when the wheels of the car do not rotate anymore but the car is still moving - this causes the tires...

Car - brake locking, stopping distance]]>

Since the gravitational acceleration varies depending on location, then how do you know if your scale is precisely calibrated? If I use a calibration weight (e.g. 100.000000 g) that was manufactured and tested around at equator where g=9.780 m/s^2, in my lab at the north pole where...

Weight measurements and gravitational acceleration]]>

How can two equal and opposite forces produce motion? [EM]]]>

I took a short undergrad module in measurement and uncertainty, intended to prepare for the numerous lab sessions and reports that would follow in the proceeding modules. In that particular...

Measurement uncertainty]]>

Consider a spherical planet of mass m and radius r

Angular Momentum of a Planet]]>

I am wondering, for the...

Using multiple mirrors in Michelson Interferometer]]>

Sound: How pleasing to the ear]]>

The Nuclear Fission process is started when the Nuclear fuels rods are submerged in coolant water to moderate the Nuclear fission process. When the Fuel rods are put close together this sets of a...

Nuclear Power Plant]]>

The tube is heated so the inside emits as a blackbody. A seperate temperature sensor attached to the tube gives the temperature of the tube.

I have a thermopile...

Experiment - Flux, Irradiance, wavelength from Temperature]]>

https://www.facebook.com/HECHOenNUE...218328082289/1950024855234964/?type=2&theater

Now, I see how the generation of energy is done in the way that a "lemon battery"...

What explains this potato light socket & battery?]]>

Also, if they did add it, do you think it would be added as a base unit or dimensionless derived unit?]]>

Multiple reflections and transmissions of light inside a cube]]>

What is the direction of the momentum density of the E-field. I have two competing feelings about it. 1) The momentum density should be parallel to the Poynting vector, and since...

Momentum density in a Divergent Beam]]>

Or maybe it was shown mathematically that the energy...

Why was the speed of light even considered to be infinite?]]>

Film is just on the top of flat object(Paper, Display, Picture, etc).

If Fresnel lens is made on top of the film, Can I magnify the object?

Thank you.]]>

thanks and regards

Uday]]>

An Integral Result from Parseval's Theorem

View attachment 207015

...

An Integral Result from Parseval's Theorem - Comments]]>

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

Physics Learning Resources]]>

Then, when I calculate the radiant...

Lambertian surface]]>

If higher temperature is correlated with shorter emitting wavelengths, how come there are incandescent light bulbs that emit yellowish light but are hotter than incandescent...

Emission spectra of different materials]]>

Longitudinal and transverse response function]]>

while i am thinking about charges,i think

consider a positive charge. And put an electron very far from it. Is there any posiblity for electron don't affect from positive charge]]>

Another of my queries is that when dispersion takes place there is a change in wavelength but not so in case of frequency. But they are related inversely. So, why does this happen?]]>

Let the distance between the two masses at time ##t## be ##d(t)##. If we set the origin of our...

Solve the positions of two masses gravitating toward each other]]>

Electric fields and circuitry]]>

How do the neutrons and U235 nuclei get out of the metal encased fuel rod...

How do Neutrons and U235 Nuclei get out of the fuel rod]]>

So, I am game developer, and one time I was using 2d physics engine to simulate motion in game. And I found out that in that engine, for...

General question about how objects move nature (discrete or continuous?)]]>

I have a simple question about capacitors. We are learning about them in class and in some questions, I seem to come up with different answers than the solution sets, always by 2. I apparently am using the area of each plate in a capacitor to derive my results.

My question is when...

Total area of a capacitor?]]>

Can Negative Mass at near Speed of Light go Back in Time?]]>

https://upload.wikimedia.org/wikipe...otopes_en.svg/715px-Table_isotopes_en.svg.png

The black squares represent stable isotopes, and columns that have no...

Is there no stable isotope of Tungsten?]]>

Halogen lamp Spectrum]]>

How can gravity be greater than the centripetal force?]]>

no REAL life = monopoles, origin of the universe, space bull, particle physics( muons,pions etc.);

PS. I am 14 years old so don't...

Real Life Uses for Maxwell's Equations]]>

I know I have to look through a book on Thermodynamics. I actually have done that some time ago and I will do that again. But the following...

Fundamental thermodynamics relation]]>

Suppose we have an infinitely tall slit of width [itex]a[/itex] and a parallel screen a distance [itex]r_0[/itex] away. Let the [itex]x[/itex] axis be...

Single Slit Fraunhofer Diffraction]]>

Well known equations in rocketry are:

Delta Velocity = Ejection Velocity * ln (Final Mass / Initial Mass )

and

Net Thrust = Mass Ejection Rate * Ejection Velocity – Current Mass *...

Rocket equation: is there an optimal thrust?]]>

What factors affect the resonant frequency?

And is resonant frequency dependent on size?

i.e. if the resonant frequency of 1 cm3 of glass is some certain value, would it be the same for a larger size?]]>

Supressed harmonics with certain initial conditions]]>

It is my impression from playing drums and guitar that when you strike a drum head or guitar string very aggressively, there is a natural "pitch...

Do drums/strings have a pitch bend when they are struck?]]>

In a nutshell, pop bottles embedded in a hut wall draw air in, and supposedly cool the air inside. As far as I can tell, they are claiming it is not just a cooling

Eco-Cooler: plausible? Or snake oil?]]>

shttps://www.youtube.com/watch?v=FhpL5h8sEHo (without the s at the beginning)

i really dont understand how the high blood pressure acts on the legs. The physics i...

Physics of a Jumping spider]]>

View attachment 206993

and here is the accompanying text

View attachment 206994

I would like to understand the "minus" signs in

- N

Basics of transformers]]>

I am planning on building my first Focault Pendulum(As a physics projject for school) and I have a few questions. I am going to purchase a cable(it needs to be smooth and friction-less around 7 feet), I also am going to need to...

Foucault's Pendulum Recreation for Physics Project]]>

I remember years ago at school memorising the derivation of the formula for pressure in the kinetic theory of gases, as explained in this Youtube video:

Thinking a little more deeply about this derivation there are two things I don't get:

1) At...

Kinetic theory of gases: rebound speed and force questions]]>

I need help with a Rigid Pendulum Calculation please]]>

Help with Python modelling of a particle in a 2D box]]>

Want accurate cartoons of EM Waves]]>

Visible magnetism? Or what? (right after a very close lightning strike)]]>

Many other...

Fourier transform and locality/uncertainty]]>

My understanding is that when light (with some frequency and polarization) hits the interface between two media (each with some frequency-dependent material properties), the Fresnel equations apply. This tells us how much light reflects back versus refracts across the interface.

I'm...

Overview of General Fresnel Equations + Complex IORs]]>

What is convection in a serpentine flow field?]]>

How to find the speed of light practically?]]>

Is what Tesla observed real?]]>

where ##C_v## is the velocity coefficient, ##g## is the acceleration due to gravity, ##h## is the height of the water above the exit hole, ##p## is the excess pressure above...

Water flow from pressurized tank - versus temperature]]>

So I was trying to work through a calculation to figure out the precession rate variation in terms of the Precession of the Equinox.

I came across the following formula from...

Help with formula to calculate the precession rate change]]>

Will...

Sound propagation with altitude/height]]>

thin slits and accuracy of Kirchhoff's diffraction formula]]>

This might be an obvious question, but that...

Lenz's Law and Induced Magnetic Fields]]>

Lets...

Aim the solar furnace up! :)]]>

There is a heat source at left side and heat is observed at point Ho after a distance L from the source. If we consider only heat transfer through conduction then this problem can be modeled by...

How to validate a code written for solution of 1D diffusion?]]>