Total energy Definition and 221 Threads

Here is a detail that makes me doubt: Homework Statement I am given the equation for a standing wave with a dependence in 't' and 'z' only... I am told that the wave is propagating in a confined space (2*2*2) m Q1. Calculate the energy density for n=1,2,3. I didn't have any pb with this...

Calculate the total energy of a geosynchronous satellite (one that orbits over a fixed spot) with a mass of 1500kg, orbiting Earth at a height of 325km with an orbital speed of 5000m/s This question is starting to drive me a little mad. First of all, the satellite can't be in a...

Is it possible to express the total energy of a damped linear oscillator as a function of time? I'm confused here. I'd like to find E(t). As the oscillation is damped, dE/dt should everywhere be negative (energy being dissipated as radiation or heat). By setting E(t) equal to zero, shouldn't I...

Question: A block of mass .05 kg is pulled .3 m from its equilibrium position and released. The spring constant is 5 N/m What is the total energy of the block-spring system? My book says E = K + U or E = (1/2)mv^2 + (1/2)kx^2. My book also says E_total = (1/2)kA(amplitude)^2. Which formula...

Q: A sinusoidal wave of the form: y = A \sin{kx - \omega t} is traveling along a string in the x direction, where A = 0.88 mm, k = 2 m^-1, omega = 25 rad/s, with x in meters and t in seconds. For this string, the mass per unit length is given by mu = 0.01 kg/m. For a length segment delta x = 1...

A solid sphere of mass 0.599 kg rolls without slipping along a horizontal surface with a translational speed of 5.07 m/s. It comes to an incline that makes an angle of 37.0° with the horizontal surface. (a) What is the total energy of the rolling sphere? Neglect energy losses due to...

The specific heat capacity of solid lead is 0.159J/g°C, the molar enthalpy of fusion is 5.0kJ/mol, and the melting point of lead is 328°C. Calculate the total energy required to change 100g of lead at 25°C to molten lead at it's melting point. I don't even know where to start, I know...

A block of mass 0.25 kg is connected to a spring with a spring constant (k) of 35 N/m. It is oscillating on a frictionless horizontal surface. It's speed as it passes through equilibrium is 1.04 m/s. What is the total energy of the system? I know that E=0.5(k)(A)^2. I just can't figure out...

I need help with this question. I can't see the motion. I have Consider a solid sphere of radius R with a charge Q distributed uniformly. Suppose that a point charge 'q' of mass 'm', with a sign opposite that of Q, is free to move within the solid sphere. Charge q is placed at rest on the...

Total energy of a dielectric sphere please help! I have a problem that I can not do after searching the net and looking through my notes and textbook. I think it is a basic electomagnetic field question but i just can't get my head around it. The question is: The electric field E inside...

An electron with speed 0.8c, has a rest energy of .51MeV. What are its mass, its momentum, and its energy (including rest energy)? ---------------------------------------------------------------------- Ok, isn't it possible to get the three answers without using the .5MeV ? I have...

Two stars with the mass and radius of the sun are separated by distance 10*r_sun, measured between their centers. A 10,000 kg space capsule moves along a line between the stars. Suppose the space capsule is at rest 1.0 m closer to one star than the other. What will be the speed of the space...

The answer to the problem is a), the orbital speed will decrease but the total energy will become larger. How is this? It's kinetic energy has decreased and the gravitational potential energy should also have decreased from this equation GM(earth)m(object)/r where r has been increased, thus...

Can some one please help me with this question: A 20 microfarrad capacitor is charged to 10V and isolated. A second uncharged 20 microfarrad capacitor is now connected to the plates of the other. The capacitors rapidly come to the same pd between their plates. What is the charge on each...

Lately there has been a lot of talk about this kinda stuff and I am beginning to understand it but I think the best way to fully understand it is if I write it out and ask you guys. Let's say that one mass is orbiting another in space and all we know is the mass of both planets and the...

This post relates into the idea of post: https://www.physicsforums.com/showthread.php?t=58918 I was talking to my physics teach and he said some thing confusing. I have a video of the ball drop and the separation; however, I do not have the clip RIGHT before the collision (with the earth)...

Hi, From knowing that the 3D harmonic oscillator has 3 degrees of freedom, how do you conclude that the average total energy of the oscillator has energy 3kT? Thanks, Ying

The question and detail: I setup the problem using energy conservation: K_a + U_a = K_b + U_b: K_a = total kinetic energy of the 3 charges when they're at rest U_a = total potential energy of the 3 charges when they're at rest K_b = total kinetic energy of the 3 charges when they're far...

Is it really zero, as suggested by some scientists, or it is slightly more or less? Any papers published on this topic?

[FONT=Tahoma]Particulars: ball has a radius of 2.5 cm a mass of .125 and is rolling across a table with a speed of .547 m/s, this table is 1.04 m off the ground. It rolls to the edge and down a ramp How fast will it be rolling across the floor? First I found the Gravitational Potential...

SETUP A Young experiment is set up using a continuous laser source of monochromatic plane waves with wavelength λ, an opaque barrier with two equal size vertical slits and a sliding light detector that can produce an irradiance graph for all of the light passing through the slits. The...