Kinetic energy Definition and 1000 Threads

A 2.53*10^(-6) C charged particle with kinetic energy of 0.0929 J is fired into a uniform magnetic field of magnitude 0.147 T. If the particle moves in a circular path of radius 3.38 m, determine its mass in kg. (answer should be within 2*10^-14 kg) The formula r=mv/qb comes to mind where r is...

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...

Homework Statement I'd like to understand Drag Force better; but school always ignores it. Thus, I'm asking this purely out of obssession. I'm picturing a scenario where a non-constant force is pushing an object horizontally, ignoring friction. But, I'd like to understand how Drag Force...

Homework Statement Two blocks move along a horizontal frictionless surface and collide head-on with each other. The mass of the first block, moving to the right with speed v is m, and the mass of the second block moving towards the left with speed 3v is 2m. After the collision, the block of...

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...

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 What % of PEg must be converted in KE in order to double the speed of a pendulum? So I have spent a couple of days trying to figure out this problem (it's a lab), and I can't seem to figure it out. I have asked my physics teacher about it, and he said the answer to 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 A projectile is fired vertically from the Earth's surface with an initial speed of 11.4 km/s. Neglecting air drag, how far (in meters) above the surface of the Earth will it go? Homework Equations (1/2)mv^2 -GmM/R The Attempt at a Solution KEi+PEi = KEf+PEf (1/2)mv^2 -...

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 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...

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...

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 Let two particles of equal mass m collide. Particle 1 has initial velocity v, directed to the right, and particle 2 is initially stationary. A: If the collision is elastic, what are the final velocities v_1 and v_2 of particles 1 and 2? B: Now assume that the mass of...

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...

Homework Statement If a proton with a kinetic energy of 6 MeV is traveling in a particle accelerator in a circular orbit of radius 0.75m, what fraction of its energy does it radiate per second? m = 1.67 * 10^-27 epsilon_0 = 8.854 * 10^-12 c = 3 * 10^8 Homework Equations dE/dt = (q^2 a^2) /...

Homework Statement The gravitational potential energy of a certain rocket at the surface of the Earth is -1.9x10^12 J. The gravitational potential energy of the same rocket 300km above the Earth's surface is -1.8x10^12 J. Assume the mass of the rocket is constant for this problem. A) How much...

I have two simple examples of potential energy and kinetic energy. First example: Imagine a book on the ground and I want to lift it.At first I apply a force just a little more than the gravitational force of the Earth so that it has some velocity. After the book gets that velocity, I keep my...

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...

Note: Please only give hints please! No answers because I want the satisfaction of solving it. 1. Homework Statement A mass M at height h above flat round and falling vertically with velocity v breaks up explosively into 2 parts. The kinetic energy given to the system in the explosion is E...

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...

We are giving a particle with mass 400 Mev/C2 and 200 MeV KE. What is the Energy of the particle? Is it 600 MeV or 200 MeV?

Homework Statement Homework Equations K.E = p^2/m The Attempt at a Solution [/B]

Hi all, I stumbled into a somewhat odd mathematical problem, so I guess I've overlooked an important detail. If I have a mass of 1kg on wheels horizontally, and apply 10N of constant force so the mass is accellerating. I assume the velocity of that mass after 1 second is approx 10m/s. Then...

Homework Statement A 4.0 kg block starts at rest and slides a distance d down a frictionless 35.0 incline, where it runs into a spring. The block slides an additional 16.0 cm before it is brought to rest momentarily by compressing the spring, whose spring constant is 429...

A rocket is drifting in gravity-free space and is observed by an external observer who is also drifting at an unchanging location using an arbitrary coordinate system. The rocket accelerates at a fixed rate using a massless photon engine that results in a negligible change in the mass of the...

Good afternoon! I would like to preface by saying, yes, this is for a project. I am only posting here to see if my method of solving is correct before I finish the project incorrectly. Homework Statement I chose two balls, mass A: .553 kg and mass B: .410 kg I recorded their collision and...

Homework Statement in circular motion (e.g. a pendulum) is the kinetic energy still 1/2 m v ^2 or is it a different equation? Homework Equations 1/2 m v ^2 The Attempt at a Solution

Homework Statement I am working on a problem similar to this one: In this solution, I do not understand what mc is, can someone explain? Also, would I follow the same type of steps if I have the kinetic energy of a photon and I need it's wavelength? Homework EquationsThe Attempt at a Solution

I am confused of how Work basically equals to Kinetic Energy...I will give an example just as way to help you help me get an idea about how it works...the example I thought of is... '' James (100 kg) jogs on a straight road at a constant velocity of 2.2 m/s for 600 seconds, how much energy does...

When doing work on the brakes of a car or bicycle, how much of that energy is actually removed from the total kinetic energy of the vehicle? What is the most efficient braking system?

Does light contain kinetic energy as it moves, or does it require mass.

Sorry If the thread name confuse you. I want to know if I want to find the Torque from deriving Kinetic Energy and the system has Object the Rotate and the rotating cause linear motion(v). Let's say it a Rolling Disc on the non-slope plane which has angular velocity ω and that ω cause it to move...

Hello everybody, My question today is: Given a molecule that has an internal degree of liberty ( let's take the ethane molecule with its internal rotation as an example), how to write the kinetic energy operator by means of the corresponding internal coordinate? Thank you guys. Konte

Homework Statement A body of mass "m" is let go from on top of a surface A, where it slides down to B(without friction). From that point on, it displaces itself on an horizontal surface 5 meters away from B, where it stops at C. Being "m" a mass in kg "h" in meters and g = 10 m/s^2 The value...

Hi! I search the way to calculate the average orbital kinetic energy like is given in :http://physics.nist.gov/cgi-bin/Ionization/bun.php?Id=AlI (here is for aluminum). I would like use the underlying method to calculate the average orbital kinetic energy for the silicon (Si) element. If you...

Homework Statement A motor lifts a block of mass 0.050kg at a constant velocity of 0.40m s-1. The current in the motor ia 85mA and the potential difference across it is 3.0V. Calculate the efficiency of the motor Homework Equations Ek = 1/2 x mv2 Electrical power = VIt The Attempt at a...