Kinetic Definition and 1000 Threads

I got acceleration by dividing force by m then replaced a by dv/dt and then integrated it to get velocity as a fxn of time and hence got kinetic energy but problem is my ans does not match with any option can someone please compare their ans

Firstly I tried defining into an equation to make the whole thing more 'tangible'. ##m_1= Paula's~Weight⋅2 = m_p⋅2## ##m_2= \frac {Dave's~weight}{2} = \frac {m_d}{2}## Before impact ##E_k1= \frac 1 2 (m_p⋅2)(0^2)## ##E_k1= \frac 1 2 (2m_p)## ##E_k1= m_p ## After Impact ##E_k2= \frac 1 2...

Hi. I searched and found no answer to this simple question: Is the spinning wheel in this videoclip keeping the same rotation (kinetic energy) when flipped upside down and back again? (if we forget about friction)

I always read that the static friction applies when the object is not moving. If it starts moving then you have kinetic friction. But suppose the case of a block on conveyor belt. The block is moving, but I was told that that friction was static friction. Or suppose the Death Wall. I've also...

Image1, the exercise. My solution: Image2, my solution The answer is .37 but I keep getting .45 What am I doing wrong?

Suppose object1 with mass m and velocity v has collided with a block. Also, object2 that has identical shape and dimensions with mass m/2 and velocity 2v has collided to that block. Since the momenta of two objects are identical but the kinetic energy of object2 is twice: Are the forces between...

Are there any instances where kinetic coefficient of friction greater than static coefficient of friction? Is this possible in nature?

Summary: I always confuse Binding Energy with Released Energy in such processes. Which one comes from mass defect? For example in a Deuterium-Tritium fusion two nuclei with lower binding energy converse to He-4 with much higher binding energy (and a neutron). The released energy is 17.6 MeV...

Summary: Integrating the 1 dimensional MB Distribution in terms of translational kinetic energy up to infinity, does not yield ##\frac{1}{2}k_BT## as it should be. The format for the 3 dimensional Maxwell-Boltzmann Distribution is ##A\cdot e^{-\frac{E}{k_BT}} \cdot g(E)## in which ##A## can be...

I don't really know how to begin this problem. I need some advice

I'm programming a game in which I'd like to simulate the real world physics of an attack using primarily medieval style weapons. Think dwarf fortress, but rather than assigning damage numbers we're calculating force or kinetic energy. Getting that much is easy enough since I can find the mass of...

My attempt at the solution... I only have problem in solving part a) 1) i calculated the spring force actingbon the table block and it is greater than the frictionnand tension force acting in the opposite direction, so by that the block will move in left. 2) now i found that which forces are...

Usually when setting up an energy equation I use the general form, (Initial KE) + (Initial PE) + (Any other work done to the body) = (Final KE) + (Final PE) ... For this I said the initial GPE and KE are 0, and the work done by the field is GMm/x (derived by integrating a force of -GMm/r^2 from...

Dear Experts, I have read from various sources that the temperature of a gas is related to the "average translational kinetic energy" of a molecule of gas. When there are molecules that support motion other than translational ,which may also have rotational and vibrational motion, How does those...

Suppose that we have two balls (1) and (2) with the masses m1 and m2 and velocities v1 and v2, respectively. Furthermore, suppose that their momentums and kinetic energies are not the same so that P1>P2 and K1<K2. Which ball is more dangerous in hitting a person.

Sadly, that's what all I could do.

If one considers the kinetic theory of gases, can a first order estimate of thermal transfer be performed by considering momentum exchange at the container's surface? I understand the basics of explaining and calculating pressure with the kinetic theory of gases, but if we assume energy is...

$$\sum F_x = T - w_x - f_k = ma_x $$ $$ T = mg\sin(\theta) + mg\cos(\theta)\mu_k + ma_x$$ $$ T = (9.8 \frac{m}{s^2}) \cdot (\sin(41^{\circ}) + \cos(41^{\circ})) + (75kg)\cdot(0.25\frac{m}{s^2}) $$ $$T = 672.91 N $$ Having found the tension force, I can find the work done by the person who's...

Imagine two black holes at great distance. They are both spatially separate and both completely collapsed to a singularity. Gravity begins to pull them together. According to the equation for the gravitation potential energy of two objects at distance… Ug = -GMm/r …These two objects begin...

(4+.9)(Wf)=(4+.63)(.27) (4.9)(Wf)=1.2501 Incorrect

Since we are looking for K total, I summed the given kinetic energy for lead and the typical kinetic energy of an alpha particle: 0.12 + 5 = 5.12 MeV. My answer is definitely wrong, but I don't how I should approach the problem.

So first I tried to use KE=1/2 x m x v^2 but then realized I didn’t have the velocity and I can’t figure out a way to obtain it. I then tried to work out the energy using a different equation, W= q x v but that left me with 1.28x10^-14 J which seemed too small. I also then have to calculate the...

I tried to find the force of friction using the the coefficient of kinetic friction with the equation F=nukmgcos Ѳ. Then I made the force of friction equal to the force of pull. I don't know what I'm doing wrong as I'm getting the wrong answer. I have attached a picture of my work.

I had a question about the equation (1/2)mv^2... Why is the velocity squared? Why not simply (1/2)mv? Does it have anything to do with the intrinsic angular momentum ie does the intrinsic angular momentum change in anyway as velocity increases in a particular reference frame leading to the...

So the equation for work is W = F * s F = m * a, so W = m * a * s Transferring this to units of measurement gives us: J = kg * m * s-2 * m Or simplified: J = kg * m2 * s-2 Transferring back to units of quantity: W = m * v2 How can that be correct? Obviously Ekin = 1/2 * m * v2. Where did that...

if lithium 7 3 captures proton, it is divided into two alpha particles. Calculate the kinetic energy of the alpha particles. the proton energy can be neglected and the mass of the nucleus of Li is 7,01601u. I only know how to write the equation: 3Li7 + 1H1 → 2He4 + 2He4 Can anyone help me? How...

Hello! I'm trying to understand the concept of escape velocity, and I know you equate the initial mechanical energy to the final mechanical energy, where the final mechanical energy is at a distance of infinity. I know that the gravitational potential energy approaches 0 as the distance r gets...

For parts A and B I used energy to find the vcom and omega, but that won’t work for C. I have an answer by combining the three formulas that use acceleration above. My answer for alpha=-5g/3r. The next two are easily solvable if you find C, but I still feel like I’m missing something. Any help...

First time poster here, and I need some experts to weigh in on a debate that I'm having on the Skeptics Guide to the Universe forum, here (https://sguforums.com/index.php/topic,51110.0/topicseen.html ). In my opinion, a few of the other posters are being pessimistic. Given recent advances in...

I understand that the work done is Change of Energy. W = ∫xixf F dx = ΔEThe force is gradient of potential energy F = -∇U (For conservative forces of course) from here, we can say that change of potential energy is W: ΔU = -W but also ΔU = -W = ΔE I'm little bit lost here.. Can you help me...

We are told that temperature measures the average kinetic energy of the molecules or atoms in a substance, but this cannot be true. If I take a jar of water and put the jar in my car and drive it aorund, it won't get hotter, though it's kinetic energy must surely be higher. Clearly, I've got...

Why is Kinetic energy a scalar quantity? I read in an article, it said, when the velocity is squared, it is not a vector quantity anymore. Can someone fill in the gaps for me? I can't quite get what that article said. And I would be pleased if you provide some other examples other than kinetic...

How small should ##\Delta T## be in a collision to be considered elastic? In elastic collisions ##\Delta T =0##, but as far as I know, just atomic collisions are considered perfectly elastic. Then, which criterias are used to considere a collision between two objects elastic?

Homework Statement A photon with an initial wavelength of 0.1120 nm collides with a free electron that is initially at rest. After the collision the wavelength is 0.1140 nm . a) What is the kinetic energy of the electron after the collision? b) What is its speed? c) If the electron is...

I am trying to derive the kinetic energy from the work and can I derive it like this ? $$W=\int Fdr$$ $$W=\int \frac {dp} {dt}dr=\int (dp) \frac {dr} {dt}=\int (mdv)v=1/2m[v_f^2-v_i^2]$$

In the derivation of finding pressure exerted by a gas using kinetic theory of gases I am not understanding why the time between two collisions is taken as the time for rate of change of momentum when a particle bounces back from the wall. please help me

Homework Statement A block starts at rest. A hand pushes the block with 6.1 N to the right across a rough surface, with 1.5 N of friction. if the block moves 1.6 m horizontally determine the following (a) work done by hand (b) work done by friction (c) the amount of thermal energy created (d)...

Homework Statement How do Initial and Final Kinetic Energy depend on each other? Homework EquationsThe Attempt at a Solution Do they remain equal? For example for the same mass m, can we write KE1 = KE2 1/2 m v1^2 = 1/2 m v2^2

I have been reading up on the kinetic theory of gases, and I'm unsure whether I have correctly understood why particle velocities become correlated after colliding. Is it because during the collision they exchange momentum and thus their velocities (and hence trajectories) are altered in a...

Homework Statement At a construction side, a small crane is raising two boxes of nails on a plank to the roof. One box has already been opened and is half full, while the other box is new. The boxes, including the nails, weight 10 kg and 20 kg, respectively, and are the same size. Diagram...

Homework Statement Two satellites in space collide inelastically. What happens to the kinetic energy and momentum? a. both are conserved b. KE conserved but momentum reduced c. KE reduced but momentum conserved d. both are reduced e. KE reduced but momentum increased Homework Equations elastic...

The answer is 3.079*10^-26 kg I tried doing E=mc^2 20*10^9*1.602*10^-19=m*(3*10^8)^2 m=3.56*10^-26 kg However when I do E=γmc^2 I get the correct answer. Is the question wrong, because isn't it 20 GeV of kinetic energy, not total energy?

When deriving the kinetic theory of gases, we take the change in momentum of a particle as it hits one side of a box and divide it by the time over which the collision takes place. The time is derived by taking the total distance the particle traveled in the box (i.e. from one end, off the side...

Earth rotates, it also orbits the Sun, the Sun orbits the galaxies and these have they’re own velocities as well. We know that the kinetic energy is measured by its velocity, and also that kinetic energy is related with temperature. By this I mean that the movement of particles are a measure of...

Hello, A generic force ##F##, which may be conservative or not, performs mechanical work which is always equal to $$W=\Delta KE=KE_{final}-KE{initial}$$ i.e. produce a change in the object's kinetic energy ##KE##. Work is essentially a way to inject or subtract kinetic energy from a system. If...

The energy component of KE is the velocity. Momentum is mass x velocity so, in a collision containing in-elasticity, if KE is lost to heat then that heat energy must have been supplied by the velocity of the object. And since velocity has been lost to supply the heat then the overall momentum...

I keep seeing a popular question asking about atmospheric pressure "crushing" us. The word "crush" throws me off. It is my understanding that air molecules create pressure due to collisions. In other words, the molecules exert pressure due to having kinetic energy - and the more molecules you...

Homework Statement "A spring with a spring constant "k" is compressed 10 cm from equilibrium. A ball of mass 100 g is at rest next to it. The spring then decompresses quickly back to its equilibrium position causing the ball to shoot forward. If the spring constant is 500 N/m, what is the...

Homework Statement You are driving with your car (of total mass: 1.2tonnes) with a speed of v=50km/h, until you see an obstacle. a) What is the kinetic energy of the car? b) When you start to brake, there is still 15m until the obstacle. What must be the size of the friction coefficient (µ)...

Homework Statement Homework Equations L = T-V For constant frequency tangential velocity is (radius)*(w) The Attempt at a Solution I need to find r(t) using the Langrangian L = T-V I just was not sure whether I am on the right track for calculating the total kinetic energy for the above...