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]]>

I have pondered this question day and night; it has often...

What is Energy... Really?]]>

Magnet + Disc+Headphones]]>

This is what I don't understand.

A) Is the red section a forced oscillation at the resonant frequency of the...

Vibrating String]]>

Static Electricity]]>

- I think there's something wrong in this question, can anybody point out the error with reasoning....

Question on energy-mass relationship]]>

What is the difference between dielectric material and piezoelectric material ?

Even Wikipedia use exactly the same figure for illustration.

I googled,

Both of them is

- material between plates

- polarization, dipole of molecule

As far as I understood from google, When material is...

dielectric vs piezoelectric]]>

Why are pollutant emissions measured in g/km?]]>

Hello,

i have a coil designed to be 2.2mH and54 ohms. When an MN60 ferrite (T-ish core) is used with it, the inductance rises to 6.1mH as expected, and the resistance...

Coil resistance increases from 54 ohms to 8k at 220kHz, why?]]>

The partition function of such a system is

\begin{equation}

Z=(1+2\cosh(\beta \,\epsilon))^{N}

\end{equation}

where each particle can be in one of three energy states:...

Negative T for a spin 1 system in the canonical ensemble]]>

body, will it conitnue to be in state of motion with constant velocity or not?...If yes then why?? (Considering all

resistances to be zero ..)]]>

Generally, I am trying to make a railgun force model. Since railguns depend on the magnetic field created around the rails (and the resulting Lorentz force) I need to model the magnetic field created by the current that flows...

Magnetic Field Computation from Thick Rectangular Conductor]]>

I'm currently on a BSc Physics course and I need some ideas for my final year project.

I'm mostly thinking about Climate and Astronomy or a mixture of both would suit me more.

Regards,

Jadaav.]]>

*** exclude...

Mechanical energy to kinetic energy storage...?]]>

A Question about Effect of Force on Rigid Bodies...]]>

So, what I know:

to get velocity...

Simple question about acceleration from accelerometer]]>

I would say it's because of the latter being a rate so...

Temperature Conversions]]>

Derivation of work done]]>

Can someone recommend a book for Optical physics? I am keen to learn rigorously some fundamental aspects of light passing through various mediums (lens). I want to understand terms such as focus, blur, aberrations etc.

-Ranga]]>

For example:

When a wave crest is above you than means perhaps 12m of water is above you.

Then a few seconds later a trough is above you so only 8m of water is above you.

So you...

Is the water pressure below ocean waves constant?]]>

Is it just the number of photons collected?

Cheers]]>

My question, if we decrease the volume, the pressure will increase due to rate of change of momentum ( we can say those two are proportional), then why can we not claim that...

Boyles law, thermal physics]]>

##

\left\{

\begin{aligned}

&C_{di}\Phi(x,r_0)=\epsilon \frac{\partial \Phi(x,r)}{\partial r}\rvert_{r=r_0} \\...

Laplace Eq. in Cylindrical coordinates]]>

How does electric current flow through a conductor]]>

Would this device(pic inside) work for boiling cold water?]]>

If that's the case, how can the compressed airs continue to...

How do standing waves continue propagating?]]>

From my understanding:

Aperture is the total diameter of the lens and numerical aperture is the ratio between the aperture and...

Aperature, Numerical Aperature and Speed of Lenses]]>

(a) Convert the following expressions and equations into...

Meaning of Slot-Naming Index Notation (tensor conversion)]]>

I noticed that when I release the cap it moves forward slightly (away from me) which I attribute to the surface being not level and my hand applying a small force. However, the cap will roll backwards afterwards (towards me).

What is causing the cap to roll back and forth? It...

Rolling a spray paint cap on a surface]]>

The estimate of the payload you can launch to Earth orbit dependent on laser power is about 1 kg per megawatt. So to launch thousand kilo...

Light beam propulsion without lasers?]]>

I have have build a wave energy collector. It consists of multiple coils in series with magnets moving up and down, following the waves underneath the unit.

My multi-meter measures anywhere between 60 and 250 milli volts...

wave energy and capacitors]]>

I taped a diffraction grating onto the lens flange (lens side, not camera side) to image some spectra- I was hoping to compare Jupiter, Spica, and Arcturus. For whatever reason, my old Sony worked...

For OmCheeto (astrospectroscopy)]]>

Use a level to test the Earth's curvature?]]>

In other words, if an electric motor being supplied with 1 Watt spins at 500 RPMs, one would need 4 watts to spin at 1,000 RPMs,...

Electric motor: power and RPMs]]>

I'm having some trouble determining what...

you've probably seen something like this...hovercraft]]>

I have measured the incident number of electrons in a channel electron multiplier at different light polarization angles (a photoelectron angular distribution measurement). The events follow a poisson distribution and as far as I know the number of electron...

Measurement and error (error estimation and propagation)]]>

Relation between sound intensity and frequency]]>

How do I convert my current dataset to the third octave?...

Calculate Third Octave Band Response from Narrowband Data]]>

Can you know which reference frame is accelerating?]]>

View attachment 204042]]>

Time to equalization]]>

View attachment 203997

View attachment 203998

This is a good start. But I want to be able to model...

Modal frequencies of a vibrating circular membrane? (DRUM)]]>

Since this missile flew into...

Missile reentry]]>

When do we know where an object is]]>

I have a question about one of the values presented in a paper, which is crucial in calculating energy transfer probability between two Yb

This is the paper:

T. Kushida, "Energy Transfer and Cooperative Optical Transitions in Rare-Earth Doped Inorganic Materials....

Question about energy transfer between Rare-Earth ions]]>

Finding torque from gyroscopic effect]]>

Then we would dig a huge area on land, again, as deep as possible. Lead the pipe to the lowest level of this huge basin we created and then use...

Getting energy from deep ocean pressure]]>

I was wondering if anyone wouldn't mind helping clarify what is occurring with a charged capacitor for me.

I understand that in a charged capacitor one conducting plate is negatively charged and one is positively charged due to the distribution or rearrangement of electrons. There...

Help clarifying capacitors, dielectrics, E field, potential]]>

Clarification between electric field and potential energy]]>

error in declination of linear regression]]>

How to write measured value with error]]>

Let's imagine I have a tank, filled with air at atmospheric pressure. This tank have a closing/opening valve.

I dive this tank at 100m under water and opened ce valve, my filling speed will be sqrt( 2*g*h) with h=100m.

Now, if i want to dive the tank (with a volume X) continuously at a...

Tank and hydrostatic pressure]]>

Sign conventions with gravity]]>

Why is Qir < than Qr? Carnot cycle and change in G]]>

the beam is vertical and i assume it will go to horizontality

this force that moved the wood beam implies a work has been done and hence potential energy has been spent

but if the beam has density 0.5 it means it has the...

Buoyancy problem]]>

Here you can see an experiment demonstrating the Gaussian gun:

Here I understand how momentum is conserved, i.e. the smaller mass of the ejected ball times its high speed is equal the bigger total mass of the...

Gaussian gun: Where does the extra kinetic energy come from?]]>

There are 2 cars, Cars 1 and 2, travelling at a velocity of 60km/h (16.67m/s) in the eastern direction with a gap of 5 metres between each other. Car 2 is in front of Car 1. Car 2 decelerates to...

Rear Car Impact]]>

My question is as follows:

I know that photons with an energy greater than the band gap can cause...

Material Heating by Light]]>

I don't get where this comes from.]]>

Reviewing for the test and there are still some things I'm not sure about so I thought I'd ask here and hopefully come across someone that can help.

I swear I knew this, but I have not been diligently reviewing as much as I should so I think I forgot and became confused.

When a...

General questions with currents]]>

I'm having trouble with solving an exercise in statistical physics. I need to argue why the average number of particles with a velocity between ##v## and ##v+dv## that hit a surface area ##A## on the container wall in a time interval ##\Delta t## is $$N_{collision}=v_{x}A\Delta t...

Ideal gas pressure from Maxwell-Boltzmann distribution]]>

Photon and electron collision]]>

I am working on a car-accident prediction model. I found the following equations here that worked in my model. However, I could not figure out how the...

Derivation of motion equations for collision detection]]>

The beginning is ok. But I can't understand how the managed to pass between (29) and (30) and between (30) and ((32), (33)).

If someone could help me, it would be very...

Brachistochrone problem with friction]]>

Basic discussion about the ionosphere]]>

New to the forum, so apologies if this is not the correct sub-category.

I am testing compliances of materials by filling balloons with different fluids. I do this by filling up a 30 mL syringe with fluid and placing it into an infusion pump set to infuse at a rate of 0.1 mL/min. The...

Difficulty extracting fluid from balloon via syringe]]>

Suppose I have a function [itex]y=f(a,b;p;x)[/itex] where a, b are known with some uncertainty and x, y were measured multiple times.

I want to find p through best fit.

I consider a, b to be gaussian variable.

I can imagine multiple ways to do this:

* I consider a, b parameters like p. I...

Best fit of a function containing costants with error]]>

I need to know a bit about lightning/discharge, in a small scale ofcourse.

I have the impression that we can somehow (with a battery) charge a metallic tip and then if we put another metallic tip close enough, a lightning will be created. Is this correct?

In addition, I would like to...

Lightning movement]]>

How much friction force does the brake pad apply to the shaft?

I am...

Finding Friction Force on a Break Pad]]>

Why is the EM spectrum contiguous instead of gapped]]>

I'm confused on several things such as the potential difference it provides and how it pushes the charges through the wire or conductor or circuit.

So when a battery comes into contact with a wire, the positive charges flows from high potential through the circuit to the low...

How does a battery push charges? Potential difference?]]>

Advice For My Physics Experiment]]>

Copper on aluminum

Copper on graphite

graphite on aluminum

I'm not sure if it matters if the order is reversed such as Aluminum on copper vs copper on aluminum..

also I've seen that...

Coefficient of friction of various materials not listed in standard references]]>

But I'm only getting the derivation by dimensional analysis.

Can anyone please provide it's real derivation?

I'll really appreciate it.]]>

I have a question about steel, for instance, silicon steel used in magnetic cores.

I was wondering about how Iron magnetises: can you align the grains/domains and heat treat it [or anything], so that it responds differently to flux one way then the other direction?

For example, say you...

Magnetic alignment of steel question]]>

Halogen lamp Spectrum]]>

A question about the speed of Light in different media...]]>

Why are refrigerators more complex than stoves?]]>

Maximum work done in a Carnot Cycle]]>