Energy Definition and 999 Threads

This problem got me kinda confused since I cannot really understand the question... who tells me how the energy dissipated in this case? Has it all transformed into heat to cause the coalesce of the two particles, or ar the two particles now merged together still traveling with a certain amount...

I'm currently taking a course where we are working to teach older physics concepts and combine them with calculus. I was assigned to work on teaching a unit about energy; for the most part, it stays relatively consistent and can be solved algebraically. Another topic in this unit is Potential...

Okay For a this is what I did. a. I'm confused about B. I understand that it has something to do with the Conservation of Mechanical Energy, but I don't exactly know what to do.

Hello, I think the only energy involved is kinetic energy. So I subtract to get the difference between two stages to find the energy cost by explosion. (0.5*9.6*14.6^2)-(0.5*0.2*2.4^2)=1022.59J However the system said that this answer is wrong, So I wondered where did I make a mistake?

Hi and thanks for taking the time to read my question. So, if i take an element and place it on top of another element and heat it, will the heat energy pass through the first and charge the other or it'll melt both elements? Thanks!

Hi all- Im new. Had a weird thought and when researched I only found the answer of bc that’s how we observe it. question. Why does energy travel in waves? Bc that’s how we see it? can anyone explain to me why energy moves in waves and not a straight line? Thanks to all who help me rid...

For an ionic lattice, the contribution to the electric potential energy from a single ion will be ##U_i = \sum_{j\neq i} U_{ij}##, which can be expressed as$$\begin{align*}U_i &= -6 \left( \frac{z_+ z_- e^2}{4\pi \varepsilon_0 r_0} \right) + 12 \left( \frac{z_+ z_- e^2}{4\pi \varepsilon_0...

I = Icm + mr^2 I = 0.5 mr^2 + mr^2 I= 3/2 mr^2 By COE, mgh = 0.5(3/2 mr^2)(w^2) g(2r) = 3/4(r^2)(w^2) 8g/3 = rw^2 = v^2 / r v = sqrt( 8gr/3) v=0.511m/s ans: v=0.79m/s

Hello there, I have heard countless times about the word energy, but I still don't know what exactly an energy is. Like for example, we know the definition of a physical quantity called velocity which by definition is change in displacement (so we can easily describe what a velocity is). We...

I do not really know the relationship between potential energy and mass difference. Isn't the difference in mass of protons and neutrons due to their quarks? (the neutron is made of two down quarks and an up quark and the proton of two up quarks and a down quark.) Please help.

Hi, I am confused about the negative aspect of these quantities. The definition in my book for gravitational potential is: "The work done to move a unit mass from infinity to a point in a gravitational field" I understand that the work done is negative because gravity is doing the work if you...

Can you compare the energy loss of electrons and protons due to the radiation they emit? In fact, I want to know which of the two loses more energy when it emits radiation.

Don't really know what they want from me

There is a large increase in ionization energy when an electron is removed from a p orbital versus when it is removed from a s orbital (and likewise when it is removed from the valence shell and from the inner shells). Why is there a smaller increase when successive electrons are removed from...

In some models of the beginning of the universe, like for example in chaotic inflation, space would stop expanding in some points, creating Hubble volumes that could experience different spontaneous symmetry breaking, which would result in different properties, such as different physical...

Hello, I am learning about solutions of the Schrodinger equation including the term of rotational energy (i.e. L^2 /2I, in its quantized form) and I was wondering if there should be another quantum term describing vibrational states of hadrons or any other composite subatomic particle, in...

Hi, I take a big number of disks to composed a circle of a radius of 1 m, the blue curved line is in fact several very small disks: I take a big number of disks to simplify the calculations, and I take the size of the disks very small in comparison of the radius of the circle. The center A1 of...

E=hf-W where W is a work function. However we know that electrons in an atom will be excited only when radiated with photons of n*f0 discrete number of frequencies. where E=hf-W is a continuous function. Is this because energy level is continuous within a conductor? If we think of only...

I know the energy is ##\frac{q²}{ 8 \pi \epsilon_{0}}( \frac{1}{a} - \frac{1}{b})##, but I can't get this result using the second equation. What I did: ##W = \frac{1}{2} \int \rho V d \tau ## ##\rho = \frac{q}{ \frac{4}{3} \pi r³}, a < r < b ## ##V = \frac{q}{4 \pi \epsilon_{0} r}## ## W =...

Ve=0m/s Vp= 0m/s Qe/Qp= 1.60E-19 Me=9.11E-31 Mp-1.67E-27 Ive pretty much gathered all of the equations I think I need to solve the problem. I just am stuck. The last step I realize that the forces would be equal to each other so I have mp x ap = me x ae but then when I try to solve for the...

First, introduce the energy – momentum equation E² = p²c² + (m0c²)². Next, just think it in natural way. If the energy – momentum equation reflects the stationary situation, then, momentum p naturally equals to zero. Then, we got E² = 0 + (m0c²)², namely: E = m0c². It can be denoted exactly...

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1. The 4th line from the left, being the aqua blue line, corresponds to a wavelength of 486 nm, as blue light has a wavelength in the range 450-495 nm. 2. This is where I am having the most difficulty, I have tried to answer the question comprehensively but I am not satisfied with my answer. In...

If someone were to talk about "a non-physical energy source" would you consider that a contradiction in terms?

I learned that the energy operator is ##\hat{E} = i\hbar \frac{\partial}{\partial t} ## and the Hamiltonian is ##\hat{H} = \frac{-\hbar^2}{2m}\nabla^2+V(r,t)## If the Hamiltonian represents the total energy of the system. I expect the two should be the same. Did I misunderstand the concept of...

Hello, I am learning how to use calculus to derive the formula for kinetic energy now, I understandthe majority of the steps in how to do this, however, there is one step where I get totally lost, I will post a picture of the steps and I will circle the part where I get lost. If you see the...

I found the total work done is: ##\frac{q^2}{8\pi \varepsilon a} + \frac{q^2}{8\pi \varepsilon b} + \epsilon \int E_{1}.E_{2} dv## The third is a little troublesome i think, but i separated into threeregions, inside the "inside" shell, between both shell and outside both. Inside => ##E_{1}.E_{2}...

a. V=-GM/r V=-6.67*10^-11*6.0 x 10^24/6.4 x 10^6 V grav = -62531250 ~ -62.5M Jkg^-1 b. To find the gravitational potential 200 km above the surface of the Earth; r=6.4 x 10^6 +2*10^5 m=6.6*10^6 V grav=-6.67*10^-11*6.0 x 10^24/6.6*10^6 V grav= -60636363 ~ -60.6 M Jkg^-1 Can I check that it is...

Potential energy is generally a function of position vector ##\vec r## and it is defined as ##\int_i^f \vec F(\vec r)d\vec r=-U(\vec r) \bigg| _{i}^{f}=U(\vec r_i)-U(\vec r_f)##, where the force is conservative. Using the fact that the integral of force is also the definition of work, I obtain...

I got the right answers but have 2 questions. My first attempt was to use Equation 2 and solve for r then use Equation 3 and solve for n. My reasoning was that the photon needed to overcome the potential energy of the atom to release the electron. This gave me n =3.44. Why was I wrong? Then...

does an electron have kinetic energy when attached to a proton? if not, what is it transformed into?

m1 + m2 = 8 COE 0.5(m1)(u1)^2 + (m1)(g)(30) + 0.5(m2)(u2)^2 + (m2)(g)(30) = 0.5(m1)(v1)^2 + 0.5(m2)(v2)^2 + (m2)(g)(16) Can you check if my eqn is correct? And can you advise what to do after this? I wanted to do COLM but i don't know what is the initial part.

I often read of photons manifesting different levels of energy. I know that energy increases as wavelength decreases and frequency increases. Are there other ways particles gain or lose energy? As water boils heat energy is transferred to the water causing water molecules to move faster and to...

A recipient (cube) of 1m³ is filled of small spheres, there are for example 1000³ spheres inside the recipient. There are also 1000³ elastics that attract the spheres to the bottom. The elastic are always vertical. One elastic for each sphere. One end of the elastic is fixed on a sphere and the...

When A hits B, COLM mV = -mVa + 2mVb V = 2Vb - Va COKE 0.5mv^2 = 0.5mVa^2 + 0.5(2m)Vb^2 V^2 = Va^2 + 2Vb^2 When B hits C COLM 2mVb=4mVc Vc = 0.5Vb COE 0.5(2m)Vb^2 = 0.5kx^2 +0.5(4m)Vc^2 sub Vc = 0.5b mVb^2 = KX^2 After that I am stuck, cause i can't find V in terms of Vb only

Hello, The sigma $(\sigma)$ molecular orbitals are symmetrical around the bond-axis while pi $(\pi)$ molecular orbitals are not symmetrical. For example, the linear combination of 1s orbitals centered on two nuclei produces two molecular orbitals which are symmetrical around the bond-axis. Such...

There are two nonconservative forces in this situation, the work done by the person and the work done by friction - they are the only sources of work that change the total mechanical energy of the mass-Earth system. The initial energy (assuming gravitational potential energy is initially 0) is...

I always read that the weight of the protons and neutrons forming a nucleus is less than the weight of them if counted as standalone particles, the difference being the "mass defect" which goes into the binding energy to hold the nucleus together. So I have two questions. 1) The elementary...

To prove: total mechanical energy is constant with time where ##E(t)## is the total mechanical energy and ##V(x(t))## is the potential energy of the object-system. $$E(t) = 1/2 mv^2 + V(x(t))$$ taking the the derivative of ##E(t)## with respect time should give 0. in the third step in the...

I am not sure if i can explain my question properly. I am studying the Generators section in the magnetism chapter. As i mentioned the statement "The rate at which work is done is exactly equal to the rate at which energy is dissipated in the resistance". When the term dissipated is used does it...

I have a lot of questions about this single concept. You don't have to answer the questions in the order that I ask, if it is convenient to answer them in a different order. 1. When the dipole moment ##\vec{p}## is in the same direction as the electric field (uniform) it has the least potential...

I recall my memory when I was a high school student. I first learned about energy from Newton Mechanics. The only forms of energy involved are kinetic energy and potential energy. At that time, energy is more like a mathematical shortcut derived from F = ma rather than a concrete physical...

hello I would like some help with the first part of this homework. for the moment i have done this: E initial=m*g*h Efinal= 1/2 m*v ^ 2+1/2I*ω ^ 2 Ei=m*g*h+1/2I*ω ^ 2 Ef=1/2*m*v ^ 2 my doubt is with the potential energy since it confuses me when there is or not...

we know ##W_g = -\Delta U## but here to find ##\Delta U## we will need another equation won't it be wrong to write $$-\Delta U = -\int_1^{0.8}mgdy$$ as this equation is derived from ##W_g = -\Delta U## and as we have 2 unknowns we will need two equations. this is a rather easy problem but I am...

We know that Planck's constant is 6.626x10-34Js. Does the energy of the same numerical value 6.626x10-34J have any special meaning. Is it perhaps the lowest possible energy or are energies less than that energy theoretically possible.

I had a thought that I wanted to share in another thread, but it wandered way off track and quite properly was closed. But I thought the separate idea that I had spawned from the old thread was worthy of posting in a new thread. I do not want to re-open the old thread, though! In flat...

Constraint: ##I=I_{1}+I_{2}## ##P_{diss,R_{1}}=I_{1}^{2}R_{1}##;##P_{diss,R_{2}}=I_{2}^{2}R_{2}## We want to minimize ##P_{diss,TOT}=I_{1}^{2}R_{1}+I_{2}^{2}R_{2}## $$f(I_{1},I_{2})=I_{1}^{2}R_{1}+I_{2}^{2}R_{2};g(I_{1},I_{2})=I_{1}+I_{2}=I(constraint)$$ $$\nabla f= \left \langle \frac{\partial...

Hello everyone! I'm new to the forum, and I've been trying to solve a problem that seems farily but I can't still convince myself of having the right (or wrong) answer. Imagine you warm up one mol of for example potassium hydride from standard temperature 298.15K to 673.15K (400 deg C). It is...

I'm reading Schutz's A First Course In General Relativity and in chapter 5 he discusses an idealized experiment in which an object is dropped from a tower, then turned into a photon and sent back up to its original height. In classical mechanics we would say that as the object falls it loses...