Recent content by Another

First of all, I do not know which question should be posted on which topic. Sorry for that. I am reading a few research papers related to VO2 smart window. The example papers that I am reading. 1. https://doi.org/10.1016/j.infrared.2019.103019 2. https://doi.org/10.1016/j.joule.2018.12.024 The...

Thank you for answering, I know that there are coefficients on the front of the polynomials but I just typed the very simple form of the equation by ignoring these coefficients (make it very easy to read and I'd like to focus on A and the unit of it) . Finally, the completely correct form of...

So, Do I have to change the unit of a constant to be the same? Thankyou very much.

I want to integrate this function ## \int_{0.8um}^{1.8um} A e^{B/E(x)} \, dx ## But A has a unit as ## 1/cm ##. Should I change ##1/cm## to ##1/um## by multiplying ##1/10^{4}## For this function, I decided to integrate using the online numerical integral, This side . I am just curious that...

I know ## L = 2md = (N_+ - N_-)d ## then ## 2m = N_+ - N_- ## So I can write ##N_+## and ##N_-## in term N and m I don't understand the factor 2 multiplying in front of N!/[(N_+)!(N_-)!] How does multiplication by the number "2" give a physical meaning?

I think because it is Water powered machine and Its only output is a single high-speed jet of water. so kinetic energy may be equal to heat energy. It could be inferred that 1/2mv^2 = delta Q So "v" is the speed of this machine.

In answering questions (a.) Why heat intake in this system is ## \Delta Q_{sys} = ( \Delta Q_{hot water} + \Delta Q_{cold water} ) / 2 ## where. ##\Delta Q_{hot water} = c(T_1 - T_f) ## ##\Delta Q_{cold water} = c(T_2 - T_f) ## I think T or T_f should be between T_1 and T_2 But why is the...

in this textbook : http://www.fulviofrisone.com/attachments/article/486/Huang,%20Kerson%20-%201987%20-%20Statistical%20Mechanics%202Ed%20(Wiley)(T)(506S).pdf ;page 20 I don't understand about Eq 1.11 come to 1.12 ? I know dU = U_V dT + U_T dV dQ = dU + p dV put dU into dQ. So dQ = U_V dT...

this figure form ( https://en.wikipedia.org/wiki/Effective_mass_(spring%E2%80%93mass_system) ) massive spring ; m K.E. of total spring equal to ## K.E. = \frac{1}{2} \sum dm_i v_i^2 = \frac{1}{2} \sum \rho dy (Vy/L)^2## V is the speed at the end of the spring and V are same speed of mass M...

this is full solution http://www.physics.drexel.edu/~pgautam/wf/PHYS517/PHYS517HW1.pdf You can see this problem in problem 2b in above link I think ##A## is modulus of vector potential ##A = \sqrt(A^2)## and A is a vector quantities of vector potential vector A = A_x i + A_y j + A_zk

I don't understand why ? ## \Psi ∇ ⋅ (A \Psi^ *) + \Psi ^* ∇ ⋅ (A \Psi ) = 2 ∇ ⋅(A \Psi ^* \Psi) ## form ## ∇ ⋅ (fg) = ∇f ⋅ g + f(∇ ⋅ g) ## Attempt at a Solution ## \Psi ∇ ⋅ (A \Psi^ *) + \Psi ^* ∇ ⋅ (A \Psi ) = 2 ∇ ⋅ (A \Psi ^* \Psi) - ∇\Psi ^* ⋅ A\Psi - ∇\Psi ⋅ (A\Psi ^*) ##

In Solution https://www.slader.com/textbook/9780201657029-classical-mechanics-3rd-edition/67/derivations-and-exercises/20/ In the question say the wedge can move without friction on a smooth surface. Why does the potential energy of the wedge appear in Lagrangian? (You can see the Larangian...

I don't understand why sometime for paper : Kramers-Kronig relations and sum rules of negative refractive index media for paper : A Differential Form of the Kramers-Kronig Relation for Determining a Lorentz-Type of Refractive Index* for paper : Comparison Among Several Numerical...

Why the velocity in spherical coordinates equal to ## v^2 = v \dot{} v = \dot{r}^2 + \dot{r}^2\dot{\theta}^2## maybe ## v^2 = v \dot{} v = (\hat{ \theta } \dot{ \theta } r +\hat{r} \dot{r} + \hat{ \phi } \dot{\phi } r \sin{ \theta}) \dot{} (\hat{ \theta } \dot{ \theta } r +\hat{r} \dot{r} +...

Why do they only think of kinetic energy of motion? Why don't they think of both kinetic of motion and kinetic of rolling energy? So. i think ## L = \frac{1}{2}mv^2 + \frac{1}{2}I \omega^2## ## L = \frac{1}{2}m(r \omega)^2 + \frac{1}{2}(\frac{1}{2}mr^2) \omega^2## ## L = \frac{3}{4} mr^2...