I have read some of the posts which discuss the meaning and mistakes involving the equation:

## m_0 = \frac{h f }{c^2}.##

My question has to do with gravitation. I would like to know if it is correct to associate to a photon with frequency f, crossing a region near a mass M, a...

Presumed mass content of photon as gravitational source]]>

I'm having trouble understanding why there is any flux moving...

Flux in magnetic core according to special relativity]]>

So I'm building a small electric skateboard, and I'm having trouble understanding how much power I need to keep the board in motion. The total weight of the board is 30Lb and I am about 170Lb. I want to maintain a speed of 15Mph when not kicking my leg. This is to be assumed on a 1...

Power needed to keep a 200lb object in motion]]>

Suppose we fill two balloons with Helium gas. One of them is filled 5 liters of He and the other to 10...

Which molecules will move faster?]]>

Why wouldn't the temperatures be different in this scenario]]>

Do you know of any Cavendish type measurements of G, in which the mass (and ~density) of the attractors (gravitational sources) are controls, and the number of particles (fermions or maybe quarks+leptons) is the independent variable?

The...

Cavendish type measurement of G with mass as a control]]>

Term: Neutral Buoyancy]]>

Please could someone provide an explanation of why the relationship between the wavelength and size of the gap is the significant factor for determining whether or not it blocks radiation in particular reference to the mesh on the door of a microwave oven. It seems very simple when a...

Faraday Cage & Microwave Mesh]]>

I have a horizontal cylinder with a ball in it. What must the initial pressure be to launch the ball at Z velocity?

P = F/A

A = Surface Area(Cylinder) - 1/2 Surface Area (Ball) = (2πrh)

F = m*a

U = - ∫ F dx

U = 1/2 mv^2 at x = h

∫ a dx = -1/2mv^2 / m at x =...

Initial pressure to launch ball at Velocity Z]]>

I'm told I can't just entitle it 'Michelson interferometer' as that gives too...

Is this a good report title?]]>

I...

In Induction Heating, what does the heat output depend on?]]>

Do all forms of light move at "Light Speed" or relatively the same.

I was told that there are many "element combinations" could be made to "illuminate light" but not all forms of light share the same...

Light Frequencies]]>

Maximum Torque in Dipoles (electrostatics)]]>

The incremental pitch-advancement of the coil's helical winding sums over its circumferential length to create an undesirable one-turn loop normal to the axis of the coil (the plane of this loop is parallel to the surface of the...

What is Returning Loop of Rogowski Coil?]]>

Electric field detector]]>

Let's say we send a short pulse of white light incident into a piece of glass (of length...

Speed of light of different wavelengths in medium]]>

Now, for my simulations i am using software that takes 4 inputs for creating aberrations onto an optical flat: m,n,R,A

m,n are the Zernike orders which is perfectly clear.

For R,A the manual says:

R: the...

Overlaying optical field with Zernike aberration]]>

How polarized test image cards work]]>

But before I go hammering away at how to exploit it, I need a better understanding of how feedback actually works

I believe that the way feedback in...

Feedback loop systems]]>

where ΔQ - is energy flow through material. K - constant characteristic...

Heat loss through conduction.]]>

Simple question - If 705 degrees F is the highest temperature water can exist as a liquid, wouldn't air pressure have to be reduced to a vacuum (or near vacuum) to remain liquid at that temperature?]]>

I have a doubt that relates to energy stored in different capacitors (when they're in a circuit). I understand how in capacitors connected in parallel, the capacitor with the biggest capacitance stores the most energy because:

E = 1/2 CV

So naturally the bigger the...

Question regarding Energy in Circuits with Capacitors]]>

in all three cases there is no battery or voltage source,right?Because I can't see any battery.But there is voltage ,then without battery how is potential difference created?I think potential difference is generated due to charged capacitors not by battery or...

Question based on a video (battery and voltage)]]>

Also, is it possible to have pure rolling without friction?

Thanks

SD]]>

I hope you all can help me so I can help my son.

If I connect a battery to a resistor and form a circuit, I know the "voltage drop"

current and resistance relate by V=IR. Now, my understanding is that in...

Can someone clarify this for me re:electric circuit]]>

Moment

[tex]\mathbf{M}=\sum_{i=1}^{4}(\mathbf{F}_i\times \mathbf{r}_i+\mathbf{M}_i)[/tex]

where F is uplift force from a propeller, and M is drag moment for a propeller.

But why they add drag moment(torque) like that? Maybe it...

Net momentum for quadrotor]]>

I am interested in finding the power of a laser diode as function of the distance

Given:

- the initial power, P
_{0}= 1mW - beam width...

Laser beam propagation]]>

Variables are ##t =## time, ##x =## space variable along road, ##\rho (t, x) =## density of cars, ##v(\rho ) =##...

On a conceptual level, what's happening in this equation?]]>