If we give an hydrogen-like atom some energy in the form of photon like less than or more than the energy difference between the two energy states of H-atom .then would it increase the kinetic energy of electron
Hi,
We have an induction heater, like a stove top one, not industrial.
I want to understand what happens when an additional load is added that it isn't intended to receive.
A plate goes on the induction warmer, it gets heated up, then removed and another plate takes it place.
What happens if the...
n the heat transfer analysis of boundary layer flow of viscoelastic fluids many researchers see the variation of temperature of fluid inside the boundary layer with Prandtl number, for which they use prandtl number 0.7, 2 , 3, 4 ..
This is what generally the researchers do..
Currently i am...
My understanding of climatology is that sulfur elements have a proven cooling effect while there is less certainty around particulate elements (which could have a cooling or warming effect). I'm wondering how changes in energy use since the 1970s might have impacted climate change, particularly...
Hello,
I am a bit confused on the relation between the Hawking effect(radiation) and the Unruh effect.
What I understood with my little knowledge is that the Hawking temperature is the temperature that is emitted at the event horizon of a black hole as measured by an observer at infinite spatial...
I wasn't exactly sure which forum I should post this question in but I felt this was the most appropriate one. So if there is a more appropriate one, feel free to relocate it (whoever is responsible for that).
I wanted strictly a scientific answer to this question. How does weight affect a...
Generally sound waves are depicted as simple sine waves, where volume is related to amplitude, and there is periodic motion. Realistically sound waves aren’t as simple. I attached a picture of a dissipating sound wave. I would appreciate if you guys could answer a couple questions I have about...
I was reading a paramedic article about pre-hospital treatment of agitated patients before or during transport to the hospital. They mention that Haldol or benzodiazepines can be effective for this (consult your local Medical Director, of course), and that it is often given in combination with...
Suppose I have two light bulbs, an LED and a halogen, but both have the same power P. Their radiation spectra are different, the LED radiating much less IR. Putting them in identical closets from which no heat may escape, will the walls and air in each come to some temperature T which, although...
I've read that when two pieces of the same kind of metal touch in space, they will fuse because there is no way for the electrons to "know" that they are in different pieces of metal.
What would happen if two different metals were to touch in space? Would electrons still flow freely between...
Hi,
For a book that I’m writing, i need to know how to describe the following, if the situation described is ever possible, otherwise I'll have to come up with another scenario.
A surge of high voltage electricity at a gas-insulated switchgear creates a flashover whose Breaker Current Failure...
How would cooling curves of a Pb-Sb phase diagram get effected if the composition had an added .5% carbon wt. concentration? My guess would be by adding an increased concentration of carbon, this would result in a increased duration of cooling needed to reach the eutectic reaction line.
Any...
Hi,
For my project I am plotting a Force vs Displacement graph using 2 analog inputs which are going to a DAQ.
The two analog inputs are coming from;
-A 5k potentiometer (for the displacement)
-A 1000 lb load cell sensor (for the force)
I would like to use a regulated 12V DC (1Amp) power...
I'm currently working on a design for a go-kart-like vehicle which involves some calculations. The engine used is a motorcycle engine and it is mounted to the main chassis via steel rods. I would like to know how the engine torque (i have an estimated value of ~45Nm) will cause stress and...
In solving a system of lenses you have to work like the second lens doesn't exist and then use the image formed by the first lens and work like the first doesn't exist, how can i demonstrate that doing so is correct?
Why is that correct?
The path that the rays make is different as is is if the...
What effect do harmonics have on wye-wye transformers with neutral grounded? What about not grounded? Also, in a wye-delta, why is there less distortion in the delta side voltage if neutral in the wye side is not connected to ground?
I understand why the Y transformers have distortion and the...
I'm a mechanic who is currently doing a study automotive engineering.
Being someone who worked on both diesel and petrol cars I know what a higher or lower air fuel ratio (AFR) will do for both engines. However I don't fully understand how the following is possible.
"Adding fuel in a diesel...
We all know that there's plenty of evidence showing that exercise does benefit cognition.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3951958/
The real question is how can I actually use this in practice to get real world results.
So if I spend 8 hours a day studying a certain subject/trade...
Dear Forum,
The title "Speed of time" is the best I can come up with. We know that time isn't constant, rather it depends on the speed at which we move as well as the gravity we are subjected to (see https://en.wikipedia.org/wiki/Gravitational_time_dilation for a reference to the latter). As a...
Sorry if this is a dupe:
An astronaut is in a windowless, sensorless starship that is drifting in an unknown location in space. There is an accelerometer aboard which reads zero. The astronaut turns on his ideal linear propulsion engine for one second, losing a negligible amount of propellant...
Homework Statement
Two parallel-plate capacitors have the same plate area. Capacitor 1 has a plate separation twice that of capacitor 2, and the quantity of charge you place on capacitor 1 is six times the quantity you place on capacitor 2.
How do the potential differences across each of the...
Homework Statement
What are the effects of changing the speed of alternator?
(elctrical synchronus generator)
Homework Equations
Ns=120*f/p;
p-poles
f-frequency
Ns-synch speed
E=4.44*f*phi*T
phi-max flux linkage
T-turns
f-freq
E- generated voltage
The Attempt at a Solution
from the above...
Hello!
I'm having a hard time finding realistic black hole simulations, but I saw one recently (black hole size comparison on youtube) that showed the following 3 black holes (attached).
I noticed that the larger the black hole, the smaller the "distortion zone" was relative to the radius of...
I know there have been discussions on electromagnets, but I think my question here is specific and hopefully quite different. Using DC power only, what amount of pull might I expect from, let's say, 48v of decent lead acid battery or batteries? It occurs to me that one could use an ebike...
In an open circuit, a voltmeter in parallel to a battery measures the EMF. Once the circuit is closed, the measured voltage drops due to both the internal and the external resistance. My question is how can the initial resistor not affect the voltage the voltmeter measures?
Additionally...
http://phys.org/news/2016-10-deadly-nearby-gamma-ray.html
How deadly would a nearby gamma ray burst be?
The original paper in Astrobiology is locked, but this summary is pretty complete.
"A burst at the South Pole fits in with theories of the Ordovician extinction because the measured...
i've been wearing a light impact sports bra in place of a normal bra for the past few months, since they are comfortable:
https://www.amazon.com/dp/B004NPTV2G/?tag=pfamazon01-20
But I've noticed that my breasts when bare have been shifting to the sides (i'm thinking that it's because the bra...
I know that SSRIs inhibit the reuptake of serotonin from synapses, and therefore cause the receptors on the postsynaptic neuron to be activated for a longer period of time. Does this have any effect on the signal sent? (for example, does it make it so the signal takes longer to process?, etc)
First, in quantum mechanics, space is not quantized. So, you can have particles of any size. It's not like the minimum size should be a space quantum. If there's no absolute 'huge' and no absolute 'microscopic', just relative sizes, then there should be no reason to assume that we follow general...
I have been wondering about space time and how it works like satillites putting corrections in there clocks by a few nano seconds a day because of gravity or lack of it! But I have also wondered about the effects of being super close to the sun and time that we observe there looking back at...
Homework Statement
I have encountered a problem in Sean Carroll's GR book, exercise 1.1
Consider an inertial frame S with coordinates ##~x^μ = (t, x, y ,z)~##, and a frame S' with coordinates ##x^{μ'}## related to S by a boost with velocity parameter ##v## along the y-axis. Imagine we have a...
Once the zener Diode is formed by breakdown of pn junction Diode, potential across Diode remains constant. If we again change the configurations from reverse bias to forward bias, is it possible to get back the normal pn junction as before the breakdown and will potential across junction be...
Hi,
I am curious as to the effects of wind on a moving person. If a person is walking at 4 mph and they encounter a 10 mph headwind, would the person feel the wind about the same as if he/she is standing still and is facing a 14 mph headwind? Likewise, if a person is running at 7 mph and...
So if an object has a velocity expressed by the vector <-3,0> and is being accelerated toward another object with the vector <-1,-2>... After one second, the object will have moved from (0,0) to (-4,-2) - calculated by adding the vectors.. My question is after the first second does the object...
Hello, I wish to ask, if a kind of nuclear attack would happen, what radiation would it be, how far and for how long? How can we know how the radioation amount would change with time? Many thanks!
its commonly stated that no particle accelerator will ever be built that can probe the Planck scale.
what about an can an event horizon telescope observe quantum gravity effects near a black hole, such as Sagittarius A*
do the various candidates of QG such as string theory LQG asf gravity...
Hi, recently this conversation came up with me and one of my friends talking about the nuclear tourists of these days which is becoming more and more part of urban exploration.
Now I tried google but I mainly got results talking about the risk and effects of radiation exposure during birth and...
First let me be clear, I am not questioning GR or the detection of gravitational waves by LIGO, I am trying to improve my own understanding of GW to the point where I can offer a graphic illustration (web video) showing what they do as they pass us to help others understand them. I started this...
I am currently reading around about squeezed light. I understand as far as the Second-Harmonic Generation (SHG) and Optical Parametric Amplifier (OPA) work, however I do not understand why the signal and idler photons that are produced by the OPA are a squeezed state.
All diagrams that I have...
Hi, I'm hoping to make small batches of synthetic minerals by compressing & heating small liquid or semi-liquid samples of sodium silicate w/ variable amounts of other salts dissolved within. As I understand it, many of these will require high pressure & temperature to form. So my strategy is to...
Greetings,
I get that increased temperature increases pressure. But does increased pressure increase temperature. For example: 1) If I press down on a table with a heavy object, does it increase its temperature. 2) Or does the pressure of the crust and the mantle of the Earth, contribute...
Homework Statement
a)a stationary railroad whistle is sounded. An echo is heard 4.0 seconds later by a train's engineer. If the speed of sound is 343 m/s, how far away is the reflecting surface?
b) If the temperature of the air increased, how would this change your answer?
Homework Equations...
So, great site.
I have a quick question that I think has a simple answer. On a snowmobile forum I visit there has an ongoing debate. The question is, all other factors being the same, does changing the lug height on a track, change the final drive ratio of the snowmobile? I think I know the...
So, i have some questions, they might sound simplistic or fanboyish even, i apologize beforehand for that! I cannot reveal anything more at this point, sorry :D
I would need some realistic assesments of a simple rod, launched from low orbit, designed to take out a city or more...
Would need in...
I've recently begun studying thermal effects. I learned that thermal energy could be transferred within an object through conduction and from a distant object through radiation. (let me know if I'm wrong here) I also learned that when matter is heated, it's particles begin to vibrate, move apart...
Reading about gravity waves got me back to thinking about relativity. And I am left with two questions to which I don't know the answer...
Question 1. Gravity waves ripple through the entire universe. They will not cause any macro scale effects because local changes to space-time are very...
Guys, I'm having trouble with some concepts on the Biot-Savart Law. Lots of texts compare this law with Coulomb Law, but doesn't affirm that B-S is only applicable on a static case (constant current). What are the real physical conditions in which Biot-Savart Law can be directly applied? Does it...
Hello to all !
In MOSFET at strong inversion electrons confined to triangular quantum well, electrons occupy only 1 or 2 lowest subbands.
and the Van Dort model gives the quantum mechanical intrinsic carrier density in inversion channel via increased energy band-gap(ΔE).
NQM = NCL× Exp(-ΔE/2kt)...