Kinetic Definition and 1000 Threads

Homework Statement Homework EquationsThe Attempt at a Solution a. ##{ P }_{ avg }=\frac { 1 }{ 2 } \mu v{ \omega }^{ 2 }{ A }^{ 2 }=\frac { 1 }{ 2 } 0.075\frac { 10 }{ 3 } { 0.35 }^{ 2 }{ (10\pi ) }^{ 2 }=15.1W## b. Not sure how to calculate that... I'm guessing it'd be some integral over 1...

[note from mentor: this was originally posted in a non-homework forum, so it lacks the homework template.] Hi guys, I need your help with the last part of following problem please. A soccer player with 70kg mass slides for 0.75 seconds on the grass to stop a soccer ball. 1) Acceleration...

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

If we have two objects forming an isolated system and their centre of mass is ##X_{com}##, we know by work energy theorem that work done on centre of mass will be ##\int F_{ext}.X_{com}= 0## as no external force is acting on the system. However, if there is internal forces between the objects...

Homework Statement Homework EquationsThe Attempt at a Solution What do I do next to work out kinetic energy?

Does electron really vibrate to produce heat energy or is it atom in whole to produce heat?

If rotational kinetic energy of a closed system decreases, another form of energy must increase for the conservation of energy of a closed system. We assume this system (a person in rotation) has these forms of energy: ΔE=ΔK (only rotational around an axis) + ΔUi (internal) + ΔEt (thermal) with...

Hello! If energy bends spacetime, then an object moving at high velocity will bend spacetime a lot around it due to its really big kinetic energy. It follows, that an object can become a black hole at extremely high enough velocities. But, since velocity is relative, we can find an observer for...

And if I can extend this further, for liquids?

<Moderator's note: Moved from a technical forum and thus no template.> A horizontal force of 80 N acts on a mass of 6 kg resting on a horizontal surface. The mass is initially at rest and covers a distance of 5 m in 0.92 s under the action of the force. Assuming there are no energy losses due...

I am going back over the topic of electricity and energy. I am just wondering within a kinetic energy generator what is the relationship between the speed of the rotating shaft and the overall electrical output of the generator. Thanks

Homework Statement I'm trying to digest the concept of change in potential energy being set equal to a change in kinetic energy. Does this relationship always hold? Please see below for more details. Homework Equations PE = mgh KE = .5mv^2 W = ΔKE = -ΔPE W = f*d The Attempt at a Solution...

Homework Statement An object of mass m = 2.3±0.1 kg is moving at a speed of v = 1.25±0.03 m/s. Calculate the kinetic energy (K = 1 /2mv2 ) of the object. What is the uncertainty in K? I am not exactly sure if I used the error equation correctly when I start using Δ(v2). Could someone verify my...

Hi everyone, I remember years ago at school memorising the derivation of the formula for pressure in the kinetic theory of gases, as explained in this Youtube video: Thinking a little more deeply about this derivation there are two things I don't get: 1) At 0:53, the video says the molecule...

http://bildr.no/view/aWc4dW95 Above is a question that I posted on a school help site. This is the answer I got: https://www.scribd.com/document/352723366/problem-about-usage-of-E-mc-2-for-v-much-smaller-then-c-ans Can you use this answer to show that the type of calculation that I tried in...

In definition and proof of kinetic energy, it uses the second law of Newton. The length of the box is L and it uses this length to define the time of applying the force on the wall. Actually this time should be only time that molecule reaches to the wall and changes its velocity. My question...

1200lb total vehicle weight 800lb total flywheel mass [4x200ea] Diameter 18.75" Flywheel RPM 3500 [120v electric motor plugged into wall] Pulley to drive wheel at 1:1 [6"pulley] or to 12' pulley Please help write the end of this story before I start. This is a "rev up" car built for...

I am proposing a piece of equipment a bit similar to Crooke's radiometer with the aim of using kinetic motion of air particles to rotate the mill, without need for an external source of EM radiation. Instead of flat vanes as in Crooke's radiometer, I propose 3-dimensional vanes in the shape of...

If I place an insulated container of gas on the edge of a turntable and then rotate the container as a constant angular velocity, what happens to the gas? Does the temperature of the gas increase? If so, how was work done on the gas?

The more I think about it the less clear the respective natures of kinetic energy and potential energy (and of their sum, the so-called total energy) become. The thing is I have the impression that once you try to go a bit further than the usual description of "scalar values assigned to systems...

Hi All, Perhaps I am missing something. Schrodinger equation is HPsi=EPsi, where H is hamiltonian = sum of kinetic energy operator and potential energy operator. Kinetic energy operator does not commute with potential energy operator, then how come they share the same wave function Psi? The...

Homework Statement Multiple choice question: The momentum of a body has increased by 25%, then its kenitic energy will roughly increase by... 1. 25% 2. 5% 3. 38% 4. 56% 5. 65% Homework Equations Pl = mv (Pl is the momentum, m is mass and v is velocity) K.E = 0.5 mv^2 The...

Can there be a system that utilizes mechanical energy to produce kinetic energy, but "storing" the mechanical energy to be used at a different time for kinetic energy? Like a bike where you pedal but don't move; that mechanical energy is waiting to be "released" by some mechanism *** exclude...

Hello. I'm looking for a purely physical explanation for an unusual event that occurred in my home. The circumstances are humorous and creepy and cause for speculation concerning the paranormal. However, I believe we have identified the true cause of the phenomenon and want to vet it against...

Homework Statement A hydrogen atom collides with another hydrogen atom at rest. If the electrons in both atoms are in the ground state, what is the minimum kinetic energy of the hydrogen atom such that the hydrogen atom at rest will have its electron in the first excited state after collision...

K= ∫mvdv = ∫m dx/dt dv = ∫m dx/dv dv/dt dv = ∫m dv/dt dx = ∫Fdx = U => K=U, why isn't this true? If it is, wouldn't that mean that Kinetic Energy is always equal to Potential Energy?

Why so? Quoted from Quantum Physics 3rd ed. by Stephen Gasiorowicz, p. 26. It was explaining why we ignore the terms with exp[iwt] when adding plane waves to form a wave packet:

I've been working on this problem for a while and here comes the problem: I'm building a balancing system for a bicycle using Gyroscopic effect (take a look at Figure 2 for more details). My system consists of 2 parts: the bicycle itself a flywheel on top of it All parameters are given. The...

Homework Statement Problem: http://imgur.com/a/Sw2zA Hi all, I was given this problem as homework and I have almost no clue on how to solve it. I have tried for some time with no luck. Homework Equations We learned about kinetic and potential energy as well as work. W = F*d W = delta KE PE =...

Hi guys. I'm new to this forum so I'm not sure if I'm posting this in the right place or correctly, but I was totally stumped on a Physics 12 question as I was studying for my exam. The question is: An explorer spacecraft is descending towards Mars using a rocket engine for braking. The...

Homework Statement The decomposition of phosphine 4PH3(g) + P4(g) + 6H2(g) is first-order with respect to phosphine with a rate constant k = 0.0155 s-l at 953 K. If the decomposition occurs in a constant-volume batch reactor at 953 K, calculate, for 40% conversion of PH3, (a) the time...

Homework Statement 5.5 MeV alphas hit Be-9 and produce carbon with a gamma. the Q value is 10.65 I have to find the kinetic energy of the carbon nucleus and the gamma and I am to ignore the gamma ray momentum. Homework Equations T = p^2 / 2*m Q = T_be + T_alpha - T_c - T_gam[/B]The Attempt...

Homework Statement A 5.72 kg block is released from rest on an inclined surface. The incline makes an angle of 25.0 degrees relative to horizontal. The block is known to be traveling at a speed of 1.33 m/s after sliding a distance of 2.60 m along the incline. How much work was done on the block...

Homework Statement In our physics course, we were studying one dimensional waves in a string. There, our teacher stated that the kinetic energy in a small piece of a string is dK=\frac{1}{2}μdx\frac{\partial y}{\partial t}^2 were μ is the linear density of the string, so he claimed that...

Homework Statement A child is initially sitting near the outer rim of a revolving merry-go-round. Suddenly, the child moves towards the center of the merry-go-round (while it is still revolving). For the merry-go-round+child system, let the symbols L and K refer to the magnitude of the angular...

Why are kinetic moments not included in the regular summation of the moments? In other words why is the equation ∑M = ∑Mk and not ∑M + ∑Mk = 0 ? I guess it would help if someone could explain exactly what a kinetic moment is, and why it is equal to the summation of the moments due to external...

Homework Statement This problem is from the 2015 AP Physics C Mechanics free response, question 3 part b. https://secure-media.collegeboard.org/digitalServices/pdf/ap/ap15_frq_physics_c-m.pdf Homework Equations K = 1/2Iω2 U = mgh The Attempt at a Solution The potential energy of the bar when...

Why don't we include the kinetic moments in the summation of the moments of a rigid body? In other words, why are the kinetic moments on the opposite side of the equation as the moments due to external forces? I understand that the math works out but it's not making sense to me conceptually...

Homework Statement Hi Guys, I don't have a particular problem that I need to solve but I need help with understanding a concept. So we agree that irrespective of mass of an object they will both fall at a same rate if there is no air resistance. However, why is it then when we increase the mass...

Homework Statement A 1.0x10^3 kg elevator carries a maximum load of 800kg Velocity = 3m/s Distance = .01km Net work = 13640J Homework Equations Force of friction = (m)(mu)(gravity) The Attempt at a Solution Gravity = friction 9.8 = (mu)(17640) .001 = mu

Hello to All ! I have a question that Whenever an electron from bulk material trapped by a quantum well that electron's 3rd dimensional kinetic energy component vanishes, But where that goes, is it added to the other 2 dimensional kinetic energy components..?

Homework Statement A child is playing with their Hot Wheel cars. They have set up a track which is initially horizontal but then ascends to a second horizontal section which is 50 cm higher than the initial track. The track is friction-less until the car reaches the upper section of the track...

Homework Statement Consider an Ocean Current flowing at 2.5 m/s. a) How much energy is contained in a cubical block of water 1m on the side. (The density of the water is about 1030kg/m^3.) b) If the flow is perpendicular to one of the cube faced, what is the rate at which current flow carries...

If you have a U-shaped pipe like the attached image, with more fluid in the left column than the right, then the fluid will level out basically because of Pascal's Law. Force on the fluid is exerted on every part of it in equal direction etc.. So when the fluid levels itself it flows across to...

Question: Calculate the kinetic energy required to accelerate a single proton from rest position to 0.9999c. The mass of the proton is 1.67*10^-27 kg. Equations Used: Ek=(mc^2/√ 1-(v^2/c^2))-mc^2 Attempt at the problem: Ek=(1.67*10^-27kg)(3*10^8m/s)^2/√...

Homework Statement What is the kinetic energy given to the proton in the decay of a neutron when: a) The electron has negligibly small kinetic energy b) The neutrino has negligibly small kinetic energy Homework Equations Q = (mn - mp - me - mv ) c2 = .782MeV Where T is kinetic energy, and...

if i connect an electric current of 30 volts to argon gas to transform it to plasma, what is the average kinetic energy of the argon particles in that plasma?

I have been pondering. Why is it that we use the rms speed in the equation Ek = 1/2 m vrms2, as opposed to just the mean speed2

I know the formulae,but really don't understand the difference

Homework Statement One effect of plate tectonics is that the North American continental plate moves across the Earth’s surface at a speed of about 1.15 cm/yr. The North American plate has an area of about 35 million square kilometers, an average thickness of about 25 km, and a density of about...