I was wondering what the relationship between the photon and the electromagnetic wave is? Is the photon traveling on that wave like a surfer is riding a wave? :-)

Thanks in advance!]]>

Q1. A parallel plate capacitor has a capacitance of 1.5pF. If its cross-sectional area

is...

Energy in a capacitor]]>

HHO Easy Recombination to get electricity]]>

Easier way to put it, if the Earth suddenly spun...

Does the rotation speed of a planet affect its gravitational pull]]>

Also what does amplitude represent in waves?]]>

For flux density so 1T = 1Wb/m^2

Often wondered about a Weber and found on a site that 1 Wb is 1 x 10^8 lines of magnetic flux! Does this sound right that an exact amount of flux lines represents 1weber? I always thought that the concept of webers was a relative idea and not...

Weber and flux density]]>

Hi folks,

I was thinking about an old physics olympiad question I read. Can't remember exactly but it was about minimising the reaction force of a skier as she took a curved path down a ski-slope. That got me thinking generally about what is going on with the...

skier, curved motion on slope/ reaction force?]]>

The game in question: Space engineers.

Machine in question: A device of my own creation that abuses the marvel of artificial gravity to accelerate a projectile at high speeds.

The...

Question about real world examples of 2.7 megajoules]]>

where N

Why don't we use simply A =

Calculating activity of a radionuclide]]>

d sin \theta = m \lambda

Which means that

sin \theta = m \lambda / d

But, what if d < \lamda so the sine value becomes greater than 1?

Will there be any interference?]]>

Why does the speed of the magnet matter in a coil?]]>

I can't the use Fresnel equations as this is for total internal reflection.

If you don't know the answer to the above question, what about the same question, but for mirrors instead?

What are the...

Energy Loss During Total Internal Reflection]]>

Can anyone please explain me - what is similar between

Nuclear fission & Nuclear fusion?

Why are only light nuclei able to undergo nuclear fusion, not heavy...

Nuclear fission]]>

Since nuclear precession...

What would happen in following condition?]]>

Analyzing signals from a radioactive source]]>

Scaling Laws and the Speed of Animals

...

Scaling Laws and the Speed of Animals - Comments]]>

]]>

This is my calculation..Am I on the right...

Force to stop a person on a treadmill]]>

Method for determining the latent heat of oils]]>

moment of inertia of two cylinders placed vertically]]>

If you know any, please advise.

Thanks,

Robert]]>

move a large amount of rocks from one place to another]]>

1) In order for a solution to count, a full derivation or proof must be given. Answers with no proof will be ignored.

2) It is fine to use nontrivial results without proof as long as you cite them and as long as it is...

Physics Challenge by QuantumQuest #1]]>

First example: Imagine a book on the ground and I want to lift it.At first I apply a force just a little more than the gravitational force of the Earth so that it has some velocity. After the book gets that velocity, I keep my...

Question About Potential Energy]]>

- Dry Air Gas Constant of
**286.9**from The Engineering Toolbox - Dry Air Gas Constant of
**287.22**from...

Why does the Dry Air Gas Constant vary?]]>

"In the UK, the Reynolds number is taken to be equivalent to:

25 043 x Q/d for natural gas; and

83 955 x Q/d for LPG."

[Q = flow rate, cubic metre per hour, d = pipe...

Can someone explain this equation for Reynolds' number?]]>

obviously the lift will go to zero as air pressure decreases.

as pressure increases, modelled by say mounting the propeller inside...

propeller thrust in restricted air flow environment]]>

Could you please help at this ? It seems book has done the calculation wrongly.

]]>

Let's say I have some sort of device that creates a lightning bolt, if I shot it at a watermelon in a vacuum or another target would it hit the target, or nothing happen because of the vacuum???]]>

A couple of old threads, people mentioned...

Effect of frequency and intensity on PE]]>

I know that 2 EM wave with linear polarisations where one wave is shifted by π, they would...

Orthogonal Polarisation in EM waves and Interference]]>

If I choose point 1 ...20kg x 1m = 20kg x 3m.......seesaw right side will fall down

If I choose point 2....20kg x 2m = 20kg x 2m.......seesaw stay horizontal

So this...

Why can we choose any arbitrary point to calculate the moment?]]>

Can the use of mathematics even describe or determines the real world? I mean, mathematical physicists always used and rely on math equations to abstract math "entities" like quantum field, virtual particles, quarks, gluons, etc. Can a physicist used math to determine the existence...

Relationship between mathematics and existing objects]]>

Where M is the mass of the mass stack in kg (0.3kg),

How to find Kepler's law from Newton's laws]]>

What could be wrong when the total inertia matrix of a robotic manipulator is non invertible when under certain values of the joint angles?

Thank you]]>

1) cause: ?

2) effect: motion]]>

eV = ½mv2

Where e is the charge of...

Thermal motion of an ionised gas molecule in an electric field]]>

Could a powerful enough laser burn through sand or ash and work effectively?]]>

This is just...

Falling Feather and ball in vacuum]]>

Actual value of normal reaction]]>

I don't know what "I" is nor do I know what "A" is but it has to do with sound waves.

May you also please correct me if I am wrong but is:

ρ = density of air

v = velocity of sound = 343 m/s

ω = angular frequency of the sound wave = 2πƒ

And also may you...

Can someone explain to me these equations of sound waves?]]>

Additionally, would the Death Star have been completely covered in solar panels?]]>

Can an Electrostatic Fluid Accelerator inflate a balloon?]]>

How to remove Ethanol from Gasoline?]]>

1. Papers

Recent Noteworthy Physics Papers]]>

I've been reading up on EM waves and I feel I'm slowly starting to get it, but I'm not entirely sure if I do, so I was wondering if anyone could help so I can be sure I'm not making some false conclusions here. I can't seem to find any answers to the less certain parts here

So as I...

Questions about light waves]]>

A 'gravity battery' could be created by using an energy source to slowly lift a large weight (using gearing or pulleys), then discharged by lowering the weight to...

Another 'Gravity Battery' Question]]>

How did they derive this formula?...

Rod falling faster than gravity]]>

I have a small confusion regarding the formula that calculates the luminous flux of a light source, which is given by:

View attachment 114990

(See this Wiki)

The ##\bar y (λ)## is the so-called luminosity function...

Lumens and the Luminosity Function]]>

I have a question for you guys and gals. I am working on a Desalination project and am ironing out questions about efficiency. What would be the most efficient temperature to evaporate water? 50, 100, 110 degrees? Does it make a difference, or is the energy required to evaporate a fixed...

Most efficient temperature to evaporate water?]]>

If you put a sealed device on a scale and place in an air tight box then fill with air pressure would the weight change of the device if there was a leak? I am trying to do a test to...

measure air leakage]]>

View attachment 114970

The way I originally learned it was just to look at it and do this :

MX1''=-KX1 -...

2 methods same answer dynamics]]>

I can't quite understand this very simple thing.

Prof Shankar's introduction to relativity on Youtube starting at about 50 minutes has a quick calculation that comes up with the Lorentz transform.

I follow the maths, no...

What Does Shankar Mean? Intro to Relativity]]>

These days I am studying rotation and rolling of bodies. We know a body can be made to rotate about any point. Let's assume that an external force is acting on the rotating body fixed about the point of rotation, and this force made the body rotates faster that is its torque produces...

Torque Equation about a point other than point of rotation]]>

X-Ray scattering in crystal]]>

Linear Momentum, in classical mechanics, is the product of the mass (the measure of an objects resistance to acceleration...

[Question] Did I figure out the Space Shuttle's momentum?]]>

Beam-powered propulsion - keeping the beam focused]]>

What about a situation when we have a sphere whose radius is R, and it's half full with...

Water pressure in a sphere]]>

How do you calculate the terminal velocity of a fluid through a pipe.

My problem includes turbulent flow, very high reynold number, and water (incompresible).]]>

but!

after that, the sound waves form a cone... what is that? is that the head of each wave being produced behind the previous wave and then blasting...

What do the sound waves look like after Mach 1?]]>

Preferably in an if.... then..... because...... statement.]]>

For now, it seems that the forces exerted on the block are balanced - thus it doesn't accelerate.

The forces exerted on the floor are, however, not balanced. The floor is not accelerating downwards, I must then...

A block on the floor - forces]]>

Gauss' gun/magnetic linear accelerator]]>

New energy creation]]>

Problems from Lev Landau's "Theoretical Minimum"]]>

Magnetic Levitation]]>

General relativity vs quantum mechanics]]>

But i dont know what causes the phenomena

View attachment 114858]]>

Conceptual Understanding for Voltage in a Circuit]]>

Time to equalization]]>

many thanks

Ewen]]>

Cheers...

Antenna inside of a cavity]]>

I need help in coming up with a function that would accurately predict what the temperature inside the box would be after say.. 5 or 10 minutes.

Basically, I need to come up with a...

Coming up with a function to model expected room temperature]]>

Superluminal speeds -- Princeton study year 2000]]>

The lens needs to be 120mm long, with its focus at a max distance of 80mm

the light traveling out of the lens needs to be parallel...

Designing a planocovex PMMA lens]]>

2)What is electricity in relation with a electron? I know it is the proportional to electric charge, but what relation does it hold? Is...

What is Electricity? Insights please...]]>

Magnetic fields and moving electrons]]>

As you can see in Picture 3 two wires parallel to each other will attract each other if the current is going in...

Magnetic field around a wire]]>

Understanding laser power terminology]]>

"Fine Tuning" constants]]>

What I don't understand is why this sharp...

Sharp ended lightning rods]]>

- By brushing a metal surface to create a matt finish, the surface of the metal becomes rougher....

How does the surface property affect blackbody radiation?]]>