Gamma ray cross sections from classical plane wave]]>

heat capacity at constant volume and density]]>

Scenario: a motorcycle is travelling down a straight highway at 100mph in 6th gear and needs to perform an emergency stop. The weather is clear and road...

The physics of braking on a motorcycle (manual transmission)]]>

Coriolis effect, Conservation of Angular Momentium, Planes]]>

the key area I wish to analyse is bar path in a squat and deadlift.

the work done against gravity is independent of path?

a lifter can either have a straight as possible body path and deviate the bar path or the lifter can alter his...

physics of moving heavy objects]]>

Charge on a conducting shell]]>

As my first post here I would like to open with a situation I have been struggling with

I have attached a simple diagram of my problem

I have 2 cylindrial N52 neodymium magnets axially aligned with each other with opposite poles facing each other....

Neodymium magnet partial shielding]]>

When a photon hits an electron, is that an event? Does that "event" have a beginning and an end?

Could the big bang be considered the only event?

Can there be any...

Do events exist in reality?]]>

Basic question - balance of forces...?]]>

The book says the friction force (F) per unit volume = $$\frac{dF}{dy}=\mu\frac{d^2U}{dy^2}$$

They say $$\frac{dU}{dy}=\frac{U_\infty}{\delta}$$

This makes sense to me, delta is the thickness in the y direction,...

second derivative of friction force question]]>

Blackbody definition]]>

Reversible processes]]>

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 hope you can pelp me.]]>

My question is what are the necessary setups?

I know that I would need a strong magnet like neodymium magnet. But, i have no idea about the formula. Lets say i...

Magnetic Levitation Formula]]>

Confusion over electric field inside a charged shell]]>

At time 0:13, light enters the plastic and exits. The light takes the path the way it does because that path provides the least time to arrive at the current exit

But why...

Why isn't there light exiting anywhere else?]]>

Is heat the cause or effect of atoms vibrating?

For heat to be hot, the atoms must be vibrating fast,but at the same time for atoms to vibrating fast they must be hot.

I know I'm...

Question about heat.]]>

Chief Ray Angle and Field of View]]>

Infact during isochoric and isobaric processes $$Q_{isochoric}=n c_v \Delta T$$

$$Q_{isobaric}=n c_p \Delta T$$...

Does efficiency alway depend on reversibility of the engine?]]>

Deriving the moment of inertia of solid sphere]]>

So the Bernoulli's EQ comes from conservation of energy. From the figure, I see that if Force 1 is greater than Force 2, the water will move to the right.

The distance Force 1 travels gives work of F

Trouble understanding energy aspect of Bernoulli's Equation]]>

Why does stretching a rubber band increase its temperature?]]>

Deriving the ionization energy of a hydrogen atom]]>

The Fibre C speckle pattern looks multimode

The Fibre A speckle pattern doesn't really look convincingly like multimode or like single mode.

A HeNe laser was used to...

Single-mode optical fibre output not Gaussian?]]>

Are continous Spectra actually discrete?]]>

can one cathode transfer electrons to multiple anodes]]>

Looking at a graph of elevation...

Atmospheric pressure vs elevation understanding problem]]>

Determining Appropriate Focal Length]]>

The effect happens, when a magnet creates a change in flux, causing a induced current in the...

Superconductors and the Meissner effect]]>

Question: Is this the same principle as probability wave which when observed reveals a particle?]]>

I'm working on a project where I am dropping an arduino with an accelerometer from ~100 ft in the air to measure it's acceleration during free fall and at impact. I need to compare my collected data with predicted models.

I have the model for free fall (just...

Modeling Acceleration at Impact]]>

A question about Vibrations...]]>

I usually find that E=σ/2ϵ0 is being frequently used but we hardly use E=σ/ϵ0.

When can I directly apply the equation E=σ/ϵ0 ?]]>

strength of materials in a reinforcing being for garage]]>

An electron accelerated through a pd of V volts will have a K.E = eV. Why isn't the K.E less than this considering that some of the work done by the field has been radiated as electromagnetic waves by the accelerating electron ?

All insights very welcome.]]>

Electric potential problem]]>

I've been doing some reading around and have come across the idea that light slows down in an dense medium as a result of the photons moving tough other particals with a slight delay however they retain all factors about them selves apron...

why do photons pass through particles with a delay]]>

I've determined and calculated the density, specific heat, thermal...

How to calculate heat dispersion through a solid copper rod?]]>

Reversibility of physical law]]>

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]]>

- I know that paul traps confine ions with the help of rapidly switching quadruple electric fields, I've heard that paul traps actually force the particle to move to the center where the electric...

Problem understanding Paul traps]]>

Why don't guns kill the shooter?]]>

A Question about Hooke's Law...]]>

Doppler effect formula confusion]]>

Image FFT and lens MTF]]>

The aim of my experiment is to calculate the magnetic field from the temperature...

Induction Heating]]>

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

i apologies at my lack of knowledge...

How can an object move without acceleration?]]>

I leaned that using a sterescopic cameras (generates 2 photos) one can measure the distance to any object in the image produced by the camera.

For example, if I take a picture of a lamp post using a stereoscopic method, I can determine the Distance from the camera to the lamp...

Stereoscopic Images and Distance Between Objects]]>

is this possible? and if yes does it need electrolyte at the anode in the middle and how to apply it?]]>

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

I have a question about electric elements and their corresponding voltages. I am looking at powering a 1500W 120VAC element out of an ordinary kettle with a DC voltage supplied by solar panels.

So, from what I understand, 120VAC represents the RMS voltage meaning that it would require...

Electric Element Voltage Specifications?]]>

I need any other tool: hypothetical speeds of ships, trigonometry, vectors, trajectories, any tool that is necessary...

Math tools in a travel to Alpha Centauri?]]>

Cherenkov Radiation and Non-Dielectric Materials]]>

in terms of oblique collisions, COM frames and laboratory frames, is this statements ALWAYS true?

"The scattering angle of the first particle in the laboratory frame is

Please elaborate if you know, thanks in advance!]]>

In my 4th year I got interested in cfd while doing a flat plate case. Fast forward to after grad and while I am looking for a job(Still looking :( ) I have been playing with Linux and open foam. I looked into astrophysics and plasma physics and such as they interest me to. So...

Are CFD codes like OpenFOAM used in other realms of physics?]]>

Lightbulb in series question]]>

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?]]>

Lorenz Gauge]]>

I have a 10 cc syringe connected to 3/32" tubing with leur lock and at the very end, it is...

How does tubing size affect pressure of syringes?]]>

Contrails -- What do we know?]]>

Helicopter torque]]>

Does anyone know of any fluid that emits light when current is running through it?

Why?

To feed to a flower, apply low voltage and make it glow.

Florescent light isn't enough and bioluminescence isn't my area of expertise so turning a flower into a LED is going to be my approach.

All tips...

Fluid that emits light when applied voltage, got tips?]]>

Looking at this I understand the the wire will experience a lorentz force because the...

Lorentz Force on a Conductor]]>

Looking for guidance on electrical impedance]]>

If we have a positron and an electron coming together and annihilating, we can always find a frame in which the net momentum is zero, which would suggest that a single photon can never be produced in such an interaction...

Annihilation and production of bosons]]>

but the sensor gives me values in LUX which is the illuminance and i need to convert them to Candela

I found this formula in wikipedia but i didn't understand...

convert from lux to candela]]>

Can we then say that each electron on average on...

Estimating # of photons/electron from magnetron.]]>

Launching a particle at the highest point inside a sphere]]>

Will the sensors in a row be triggered at the same time? If they are, what does it mean for the field?...

Fields and motion]]>

But I'm not sure I grasp this completely. Why is quantum mechanics linear while...

Linear and nonlinear physical theories]]>

Getting straight to the point, what is the difference between

Please be as specific as you can.

Thank you.]]>

Humidity and discharge]]>

Calcuating retinal irradiance from the sun]]>

I am working on a senior project right now and I need some assistance with determining the torque required to rotate an arm with a propeller attached to it.

View attachment 196002

Any of the 4 arms can be rotated to control the direction of travel. The idea is the control system...

Senior Project - Quadcopter with Rotating Arms]]>

$$\nabla \cdot \bf{E} = 0 \\ \nabla\cdot B=0 \\ \nabla \times E=-\frac{\partial B}{\partial t} \\\nabla \times B=\mu \epsilon \frac{\partial E}{\partial t}$$

Wave equation is $$\nabla ^2 \bf{E}=\mu \epsilon \frac{\partial^2...

Solutions of wave equation but not Maxwell equations]]>

What does it mean for a particle to vibrate?]]>

I know a capacitor in a circuit acts as a break when it is fully charged, but does the battery continue using energy to keep the...

Does a battery exert energy keeping a capacitor charged?]]>