Kinetic Definition and 1000 Threads

Homework Statement [/B] I have the following expression: $$S=T+V$$ $$T=\frac{m}{\tau_0+it}((x_1-x_0)^2+(x_2-x_1)^2)+\frac{m}{2(\tau_1-it)}(x_2-x_0)^2$$ $$V= \frac{(\tau_0+it)}{2}(\frac{k_0 x_0}{2}+\frac{k_0 x_2}{2}+k_0 x_1)+(\tau_1-it)(\frac{k_1 x_0}{2}+\frac{k_1 x_2}{2})$$ The main goal...

Homework Statement How much kinetic energy is in electron volts? Homework Equations Kinetic energy = 1/2 mv2 1 electron volt = 1.6 x 10-19 J The Attempt at a Solution [/B] It's a bit unclear to me what the question is asking, since no context at all is given. It's one of the questions in...

Homework Statement The question gave a force applied on a block as well as a distance. It also gave the work done by friction which was negative. The question was to find the change in kinetic energy.Homework Equations Wnet = change in KE The Attempt at a Solution I found the work done by the...

Hi. In all of my question, I mean degrees celsius when I say degree. Think we have a 0 degree ice. we give some energy to it (by a heater) and all of it get into a 0 degree water. How does the kinetic and potential energy of the molecules change? In the book in which I saw this question, it...

Homework Statement I am having trouble with Microsoft Excel formulas to obtain the correct data for Kinetic Energy 2 initial, KE1 final, KE2f, KEi, KEf, total KE and total KE% Homework Equations Microsoft office uses equations such as =(A2+B2) and I need to determine what is the appropriate...

Hi guys, Yesterday I sat down, and just for fun, decided to calculate the coefficient of kinetic friction for the all electric Ford Focus. I keep getting the wrong answer, and it is driving me crazy. Here are the facts. Battery: 23 kWh. Curb weight: 1,651 kg. Maximum travel distance before a...

Homework Statement From a physics multiple choice test: "A car is raised to a height of 10 meters. The car is at rest both before and after it has been lifted. The mass of the car is 900 kg. The total work that has been done on the car during the move is" (The right answer is: zero). Wnet...

Homework Statement B is 10kg C is 20kg can I find a lagrangian for this system? If so how? Diagram: http://imgur.com/j811rzw Homework Equations L=T-V Kinetic = .5mv^2 Potential = mgh The Attempt at a Solution I know the kinetic energy must be 0 right? How could I find the potential?

Hi everyone. Given: an asteroid with the mass of 50,000,000 kg, which is moving with the velocity of oh-my-god particle -- 99.99999999999999999999951% of c. Due to relativistic effects, its total kinetic energy will be 1.44 E+36 Joules (Lorentz factor = 3.2 E+11). A hypothetical particle...

Homework Statement Homework Equations L = IW RKE = .5IW^2 The Attempt at a Solution Since the two solid spheres have equal radii and same angular momenta, except that the mass differs, i think that the inertia is equal. However, since sphere A is more heavy, it would spin slower than sphere...

Kinda looking to confirm what I already suspect. All things being equal, if two objects have the same kinetic energy, does the fact that one is larger and heavier than the other (although at a slower velocity) mean anything? Specifically when comparing bullets. One bullet .451" in diameter...

<< Mentor Note -- Two threads on the same subject have been merged >> I am a junior enrolled in IB Physics at the standard level at my high school. As a part of the curriculum we must perform an Internal Assessment (IA) which involves performing an experiment and performing calculations and it...

Homework Statement Homework Equations W = Fk d cos θ Fk = FN μκ The Attempt at a Solution Here's my work : m = 1 kg vi = 10 m/s vf = 0 m/s xi = 0 m xf = 0.1 m d = 0.1 m k=60 N/m μκ=? The work done be the frictional force : W = Fκ d cos θ = FN*μκ*d*cosθ = mg μκ d cos 180 =...

Homework Statement Homework Equations W = ΔUg + ΔkE + ΔUs KE = 0.5 m v^2 Ug = m g h Us = 0.5 k x^2 The Attempt at a Solution k = 60 N/m vi=0 m/s (" the block is released from rest ") xi= 0 m/s ( "the spring is unstreached") vf= 0 m/s xf= 0.2 * sin 37 = 0.2*0.6 = 0.12 m d= 0.2 m...

I have a question about momentum vs kinetic energy. For example, a block C with velocity Vc and mass=2m hit a block B with mass=m at stand still on a LEVELED frictionless track( no change of potential energy). The two block stick together and move at velocity Vcb. Find the relation of Vc vs...

Homework Statement : [/B] A stationary horizontal platform is free to rotate about its vertical axis. The radius of the platform is R=1.6m and its moment of inertia is 660 kgm^2. A 43 kg boy jumps on the rim of the platform with the velocity 2.2 m/s tangential to the rim. What will be the...

Homework Statement Two blocks with masses 1 kg and 4 kg respectively are moving on a horizontal frictionless surface. The 1 kg block has a velocity of 12 m/s and the 4kg block is ahead of it, moving at 4 m/s. The 4 kg block has a massless spring attached to the end facing the 1 kg block. The...

Homework Statement Homework Equations Total Ke initial - Total Ke final = lost KE P= m1v1 + m2v2 The Attempt at a Solution Initial P : sqrt((0.08*50)^2 + (0.06+50)^2) Final P : (m1+m2)vf = 140vf Initial P = Final P and solve for vf , vf = 0.0357 KE initially : .5(0.080)(50^2) +...

Homework Statement A pulley with a radius of 3.0 cm and a rotational inertia of 4.5×10^-3 kg·m2 is suspended from the ceiling. A rope passes over it with a 2.0-kg block attached to one end and a 4.0-kg block attached to the other. The rope does not slip on the pulley. At any instant after the...

Hi everyone, hopefully someone will be able to point me in the right direction with this problem, I get as far as combining the two equations together and no matter how I rearrange them they don't seem to cancel nicely and leave me with an awful quadratic, I can find vx, but the question...

Homework Statement The bearing of a rigid pendulum of mass is forced to rotate uniformly with angular velocity (see Figure P. 1.32). The angle between the rotation axis and the pendulum is called θ.Neglect the inertia of the bearing and of the rod connecting it to the mass. Neglect friction...

Homework Statement A circular disc of radius 25 cm and mass 0.5 kg is revolving in its plane with an angular velocity of 4 radians per second. Find A) its kinetic energy of rotation, and B) its new angular velocity if a mass of 10 kg is suddenly fixed on the rim of the disc. Homework...

Homework Statement If I have two current carrying conductor carrying current is same direction, they move towards each other so kinetiisc energy increases. So which force does work here? Homework EquationsThe Attempt at a Solution I know magnetic force can't do work, is work done by some...

I'm a bit confuse. In chapter 15, of Conceptual physics by Paul Hewitt: "Temperature is related to the random motion of atoms and molecules in a sub- stance. (...) More specifically, temperature is proportional to the average “trans- lational” kinetic energy of random molecular motion (motion...

Could anybody explain what happens at the molecular level when one of the two bodies in a contact starts moving w.r.t other, i mean in this process what causes kinetics friction force, i tried myself to think of it but i could not come up with any, so please help me.

Assume a person is at space, and assume there's no friction or gravitational force in that space. The person has a bow and arrow. He stretches the arrow on the bow, and then shots the arrow out in the space. Since there are no friction and gravitational force in that space, the arrow will have...

A mass m is attached at the end of the string. The mass moves on a frictionless table, and the string passes through a hole in the table, under which someone is pulling on the string to make it taut at all times. Initially , the mass moves in a circle, with kinetic energy [E][/0] . The string is...

Homework Statement Rank the cases from maximum Kinetic Energy (KE) to lowest KE. State any ties. Briefly, explain your ranking. Case 1 has mass M and amplitude A Case 2 has mass 2M and amplitude A Case 3 has mass M and amplitude 2A Homework Equations 1. E=\dfrac{1}{2}kA^{2} 2...

Homework Statement A solid sphere of mass m=2.5 kg is rolling at v=5.3 m/s. Calculate the transitional kinetic energy, rotational kinetic energy, and the ratio of the two (Rotational/ Transitional). Homework Equations [/B] Inertia of solid sphere = 2/5 mR^2 (where R is the radius and m is the...

Homework Statement A 2.79-kg block is placed on a rough surface inclined at 28.1°. The block is launched at a speed of 3.87 m/s up the incline, and comes to rest after sliding 0.969 m up the incline. Find the coefficient of kinetic friction between the block and the incline. Homework...

Homework Statement A sled of mass m is given a kick on a frozen pond. The kick imparts to it an initial speed of 2.20 m/s. The coefficient of kinetic friction between sled and ice is 0.150. Use energy considerations to find the distance the sled moves before it stops Homework Equations...

Homework Statement Homework Equations W = ΔKE W = KEf-KEi The Attempt at a Solution W = .5mvf2 -.5mvi2 I know that final KE for A is 4 times the KE of B because for A ... KEf = 1/2 m (2v)^2 4KE = 1/2 m v ^2 for A I don't know what initial KE for both of them are... so how do i know if that...

If you had two masses, m_{1} and m_{2}, and you released them in space infinitely far apart, their kinetic energies would satisfy \frac{1}{2}m_{1}v_{1}^2+\frac{1}{2}m_{2}v_{2}^2=\frac{Gm_{1}m_{2}}{r} if they met with a distance r between their centres of mass. This equation therefore tells you...

Homework Statement In the photoelectric effect it is generalley assumed that all the energy is given as kinetic energy to the electron while the atom is neglected. Do not neglect the recoil kinetic energy of the atom and calculate the kinetic energy of the photoelectron and the ionized atom and...

A system is defined as two connected masses in an atwood machine and the earth. How do I find total kinetic energy in a system where more than one object is moving (or is only one object actually moving since the two masses are connected with a string? idk) This is an isolated system so... ΔK...

A system is defined as two connected masses in an atwood machine and the earth. How do I find total kinetic energy in a system where more than one object is moving (or is only one object actually moving since the two masses are connected with a string? idk) This is an isolated system so... ΔK...

Homework Statement A 191Os nucleus decays via β- emission to an excited state of 191Ir at 171 keV. What is the maximum kinetic energy of the electron on the β spectrum? a) 0.134 MeV b) 0.143 MeV c) 0.171 MeV d) 1.859 MeV Homework Equations 191 Os = 190.960928u 191 Ir = 190.960591u...

I have the problem below. I know that net work is equal to the change in kinetic energy which is Wnet= 0.5mv^2-0.5mvi^2.I also know that the work by force of gravity is the same for both objects. I don't understand why the objects would be the same speed at the finish line.

Homework Statement This is a lab I did for physics. In this experiment, a glider starting from rest on an air track is attached to a string. The string is drawn over a pulley with a mass hanger tied to the other end. Work is done by gravity which results in a gain of kinetic energy of the...

Good Afternoon Is it correct to calculate the force of a point charge by relating the force to the kinetic energy and this with its derivative? I have the graphic V/r (Velocity Vs Space), want to calculate force, relate work with force in this way: W=ΔEk, in my case the kinetic energy initial is...

Homework Statement How did they get mv^2? Where did the 1/2 go? I tried working out the equation below the question and I ended up getting (1/2)mv^2. Look at the image to see. It's the rotational kinetic energy formula. Homework Equations It's in part 1 The Attempt at a Solution It's in part 1

I found a problem and I'm having one question, it goes like this: A box of 5 kg is being dragged across the floor with a horizontal force of 40 N. If it starts at rest and it begins to accelerate at 3 m/s2 (constant acceleration), find: A) The coefficient of kinetic friction B) Supposing that...

I'm having this discussion with my engineering peers: A ball is sitting on top of a train traveling at, say, 10m/s. The ball has mass of 2kg, for simplicity. The ball's kinetic energy KE relative to ground zero is 1/2 m v^2, or 100J. A person riding on the train picks up the ball and tosses...

Homework Statement A 10 g bullet is fired at 200 m/s into a 1 kg block after which they slide together 2 m on a horizontal surface. Determine the coefficient of kinetic friction between the block and surface. Homework Equations ##M_AV_{Ai} + M_BV_{Bi} = 0## ##WNC = ΔE## The Attempt at a...

Homework Statement A constant force F pulls a rope vertically upward. The rope is lifting a block of mass M, to which it is attached. The rope is of uniform composition, and has mass m and length L. Find the tension in the rope at a position y along its length. (The tension will not...

Homework Statement 1. [/B]The only force acting on a 4.0 kg body as it moves along the x-axis varies as shown in the figure. The velocity of the body at x = 0 is 7.0 m/s. c) What is the maximum kinetic energy attained by the body between x = 0 and x = 8 m? Homework Equations Work = delta K K =...

Homework Statement A boy pulls a sled (mass m=59.2 kg) along the ground using a force of magnitude F = 586 N inclined at an angle of θ=37.3° to the horizontal. There is friction between the sled and the ground with a coefficient of µk = 0.205. If the sled starts at rest, how much kinetic energy...

Homework Statement Velocity of centre of mass of two particles is v and the sum of the masses of two particles is m. Kinetic energy of the system - (A) will be equal to ½mv² (B) will always be less than ½mv² (C) will be greater than or equal to ½mv² (D) will always be greater than ½mv²...

Homework Statement [/B] atom traveling at 1.00% the speed of light has a KE of 2.016x10-16 kJ. Identify the element. Homework Equations [/B] KE = .5mv^2 Hv= binding energy + KE The Attempt at a Solution [/B] Ok. So I plugged into velocity and me to find my mass and got like 4.48E-26 g. So I...

A 10.0 kg box rest on a horizontal board. One end of the board is slowly raised to 12.8° with the floor, the box slides at a constant velocity. (Use this information to find the kinetic coefficient). Find the magnitude and direction of the acceleration of the box when the board is raised to an...