Recent questions in Physics

Mazcud Cadeh
2022-05-09

If all solid blocks have the same mass, which solid has the smallest density?

Frame of reference
Answered

Ashley Fritz
2022-05-09

$S\le \frac{2\pi kRE}{\hslash c}$

where $E$ is the total mass-energy. That seems to imply that the presence of a black hole in the region is dependent on an observer's frame of reference. Yet, my understanding is that the Bekenstein bound is the maximum entropy that any area can withstand before collapsing into a black hole.

Does this mean that the existence of black holes is observer dependent? Or that even if an observer does not report a black hole in their frame, one is guaranteed to form there in the future?

Frame of reference
Answered

Elle Weber
2022-05-09

But when the car is driving in circles at a constant speed, in the non-inertial frame of reference there is a force acting on the car, which is the centripetal force. Why isn't this frame of reference like the above, not having the acceleration found in their each respective inertial reference frame? Why can't we have a non-inertial reference frame(due to rotation) whereby there is no centripetal force, subsequently eradicating the need for a centrifugal force?

Wien's displacement law
Answered

Deshawn Cabrera
2022-05-09

Why does the area under Wien's displacement graph give Stefan-Boltzmann law for a black body?

I couldn't find any proof of this. (I could just find this expression). I am not aware of the function of Wien's displacement graph as well (I just know that it is between Intensity and wavelength emitted by a black body).

Is there a mathematical way to prove this?

Wien's displacement law
Answered

bedblogi38am
2022-05-09

This is a question relating to Wien's displacement law for the Planck function. As we all know frequency and wavelength are related to the speed of light by:

$\nu \lambda =c$

However, why is it that:

${\nu}_{\mathrm{p}\mathrm{e}\mathrm{a}\mathrm{k}}{\lambda}_{\mathrm{p}\mathrm{e}\mathrm{a}\mathrm{k}}\ne c$

Any explanations would be very much appreciated.

To all of the people wanting to know where this statement came from. It hasn't come from anywhere specific, is it a well known fact of the Planck function. ${\lambda}_{\mathrm{p}\mathrm{e}\mathrm{a}\mathrm{k}}=0.290{T}^{-1}$ cm K and ${\nu}_{\mathrm{p}\mathrm{e}\mathrm{a}\mathrm{k}}=5.88\times {10}^{10}T$ Hz K${}^{-1}$

Special Relativity
Answered

studovnaem4z6
2022-05-09

Classical mechanics can be understood as the limit of relativistic mechanics $R{M}_{c}$ for $c\to \mathrm{\infty}$.

Classical mechanics can be understood as the limit of quantum mechanics $Q{M}_{h}$ for $h\to 0$.

As a limit of which discrete geometry ${\mathrm{\Gamma}}_{\lambda}$ can classical mechanics be understood for $\lambda \to 0$?

Nuclear Fission
Answered

William Santiago
2022-05-09

This is I suppose quite a precise question about Nuclear fission. What produces, aside from U-235, via a fission process, Cs-137?

Does any isotope of Actinium, for example, undergo a fission process and break into Cs-137 and something else?

Is there any way for me to easily figure this out for myself?

Many thanks.

Nuclear Fission
Answered

kazue72949lard
2022-05-09

Why do only heavy radioactive elements perform fission? I mean what's so special about heavy elements which makes them ideal for nuclear fission?

Also why do only neutrons show fission/fusion and why can't electrons preform fission/fusion?

Nuclear Fission
Answered

bedblogi38am
2022-05-09

It was my doubt and I thought it may be electric potential energy which is responsible for energy release in nuclear fission and by bombarding neutron we only provide energy to nucleons to cross equilibrium point (Felectric = Fnuclear) then it is spontaneous separated because of excess electric force, energy stored in electric field is released when it separates. Is it true? If yes then with this approach please explain why in lighter elements energy supplied is more than energy released in case of fission?

Wien's displacement law
Answered

arbixerwoxottdrp1l
2022-05-09

Wien's Displacement Law stated that for a blackbody emitting radiation,

${\lambda}_{max}={\displaystyle \frac{1}{T}}$

where $T$ is the temperature of the body and ${\lambda}_{max}$ is the maximum wavelength of radiation emitted.

Due to the relationship between wavelength, frequency and the speed of light, a value of maximum wavelength would give a value of minimum frequency, and vice versa.

I then saw on the Wikipedia page for Wien's Displacement Law that

${f}_{max}={\displaystyle \frac{\alpha {k}_{B}T}{h}},$

where $\alpha =\mathrm{2.82...}$, ${k}_{B}$ is Boltzmann's Constant, $T$ is the temperature of the body and $h$ is Planck's Constant.

How can this relationship for maximum frequency be shown?

Nuclear Fission
Answered

britesoulusjhq
2022-05-09

Can an unstable atom undergo both nuclear fission and radioactive decay?

Other than the fact that that fission has to be initiated is there a difference between the final stability of the atoms?

Half Life
Answered

Jayla Faulkner
2022-05-09

Balmer Series
Answered

garcialdaria2zky1
2022-05-09

Special Relativity
Answered

Jace Wright
2022-05-09

Frame of reference
Answered

revistasbibxjm87
2022-05-09

Frame of reference
Answered

Logan Lamb
2022-05-09

de Broglie Equation
Answered

Hailee Stout
2022-05-09

Do the properties of the waves (wavelength,frequency) emitted by a particle or object depend upon the velocity, or as to say its kinetic energy? Is the De Broglie equation $E=h\nu $ applicable to matter waves as well?

de Broglie Equation
Answered

rynosluv101wopds
2022-05-08

Just wondering if anyone can help me understand the basic principle of quantum theory.

De Broglie's equation allows one calculate the wave length of the physical object, following the fundamental wave-particle duality of quantum theory.

$\lambda =h/mv$

Since velocity $v$ is always relative to the reference frame of observer, does it imply that the wave property is not inherent but displays itself differently to different observers?

The majority of Physics equations are not overly complex since they are based on questions that are either related to some theory or focus on a specific experiment. You will find a plethora of answers that will help you understand the main concepts from college physics to more complex engineering tasks that are quite specific. If you are dealing with equations, the solutions will let you compare things to what you have and find an answer. There will also be questions that are more verbal in nature, meaning that they go beyond the formulas, so ensure to check them, too!