Mechanics (Greek: μηχανική) is the area of physics concerned with the motions of physical objects, more specifically the relationships among force, matter, and motion. Forces applied to objects result in displacements, or changes of an object's position relative to its environment.
This branch of physics has its origins in Ancient Greece with the writings of Aristotle and Archimedes (see History of classical mechanics and Timeline of classical mechanics). During the early modern period, scientists such as Galileo, Kepler, and Newton laid the foundation for what is now known as classical mechanics.
It is a branch of classical physics that deals with particles that are either at rest or are moving with velocities significantly less than the speed of light.
It can also be defined as a branch of science which deals with the motion of and forces on bodies not in the quantum realm. The field is today less widely understood in terms of quantum theory.
Hi everyone I'm Justina. I'm excited in joining physics forums and I'm high school student who is interested in Quantum mechanics a lot .I used to spend lot of time on knowing Quantum mechanics and i learnt few little things. And this is my first time, joining an online community hope I will...
Let’s consider that the total energy of this system is represented as ##E=-2mB##.
Question 1: how many microstates correspond to this energy level?
We have ##2^4=16## microstates.
++++ Total magnetic moment: ##4m## Energy: ##-4mB##
- - - - Total magnetic moment: ##-4m## Energy: ##4mB##...
I am trying to solve this problem without using energy conservation. How can I solve this using the 2 body system and center of mass.
I know that in order for mass m at the bottom to be slightly off the ground the reaction force must be equal to zero. I don’t know if the reaction force before...
So at first I tried to express the potential energy as a function of x, y and z, but since I'm not quite sure about the geometry of the situation, I decided to separate out the potential energy into three components: ##V_x, V_y, V_z## (I'm pretty sure this is valid because in the partial...
I found the internal force Vxy 25 +6 =31kn. , bending moment Mmin -qb2/2 , M min- 14 kNm. delta =M/W I can't find Mmax and tau= V/As. So I need help to find Mmax and As wall area, how to find.
I can write
$$\psi(x,t_0) =\frac{1}{\sqrt{2}}(e^{\frac{-iE_1}{\hbar}t_0}\psi_1(x) +e^{\frac{-iE_2}{\hbar}t_0}\psi_2(x))$$
for the second coefficient to be -1 i need ## -1=e^{-i\pi}=e^{\frac{-iE_2}{\hbar}t_0} ## so ##t_0=\frac{\pi\hbar}{E_2}## and the above equation becomes
$$\psi(x,t_0)...
[Rewriting this as per the suggestions. Thanks once again.]
I won't be using the Lagrangian because it was never explicitly stated that I have to so I'll just use conservation of energy.
$$ T = \frac{1}{2}mv^2 = \frac{1}{2}m(R\dot{\theta})^2 = \frac{1}{2}mR^2\dot{\theta}^2 $$
$$ V = mgy =...
Anyone read these books and care to share their thoughts?
https://www.amazon.com/Constructing-Quantum-Mechanics-Scaffold-1900-1923/dp/0198845472/?tag=pfamazon01-20
https://www.amazon.com/Constructing-Quantum-Mechanics-Arch-1923-1927/dp/0198883900/?tag=pfamazon01-20
Homework Statement: Practical examples of Hamiltonian Mechanics sought
Relevant Equations: Hamilton Jacobi Equations, MTW
Hi,
I'm currently a bit stuck on Box 24.2 in MTW. I really need to get a better understanding of Hamiltonian Mechanics to be able to work my way through this and I...
Hi all currently got a lagrangian function which i've found to be :
\begin{equation}\mathcal{L}=\frac{1}{2}m(\dot{x}^2+\dot{y}^2+4x^2\dot{x}^2+4y^2\dot{y}^2+8xy\dot{x}\dot{y})- mg(x^2+y^2)
\end{equation}
Let us first calculate
$$(\frac{\partial L}{\partial \dot{x}})$$ which leads us to...
Eddie Hall is the current world record holder in the deadlift, a powerlifting maneuver in which a weighted barbell is lifted from the ground to waist height, then dropped. The figure below shows a side view of the initial and final positions of the deadlift.
A side view of the initial position...
I think the first part is F = mxa? But given the jib is resting on a turntable at a certain distance, does that mean the longer and shorted ends experience different loads? Especially when the shorter end has a 16T counterweight?
The second part, I have no idea how to calculate this nor the...
So I think the mass can only move in two "coordinates" the axis of which the mass is connected to ##k_1## and the axis connecting it to ##k_2##. Therefore, the D.O.F is 2. I don't understand what it the meaning of "variables of integration" What does it mean?
Apart from that, I attempted to...
Why he said that beacause space's propertiy is the same in both direction, so L=L(v^2), or do I misunderstand him incorrectly?
btw this conclusion appears in somewhere like page 5 and its about Galilean principle of relativity.
These are the questions I am failing to comprehend despite their very basic nature
This is the wonderful support from the book explaining how to get the answer ! (It just gives you the answer no working out which is annoying)
I
The Twisted Metal video game series includes a character aptly named Axel, whose vehicle is just himself strapped to a pair of tractor wheels. This is the guy:
Most of my friends assume that in real life, he probably wouldn't be able to drive anywhere unless his feet were incredibly heavy, so...
I am working on an electrical engineering project. However, I have come across a specific mechanical engineering problem. I have attached an image to describe what I want to do. I have primarily a stator core (made out of electrical steel laminated sheets) named part number "1". I have a...
I was going through the stress-strain curve and I realized that strain is taken as the independent variable and stress as the dependent variable. In reality is this true or is it the other way around?I saw a lot of answers on Quora that say that strain is the cause and stress is the effect. But...
Here is my attempt at the solution:
a) The apparatus may only experience acceleration ##a > g## while in contact with the spring. Since the spring exerts the greatest force when it is the most compressed, the apparatus will undergo the greatest acceleration at that point. So Newton's second...
Calculations with 1:
T1sintheta + T2sintheta = W
T1costheta = T2costheta
Calculations with 2:
Wsintheta = T1
Wcostheta = T2
These are not equivalent. Can someone point out the flaw in my logic?
Edit: System is in equilibrium!
vA = 3u/4 and vB = u/4, and 1/8 KE is lost. I can't get to these answers however: for the first part, I got to u = vA + 3vB using conservation of momentum, and the fact that particle B is at an angle, hence I would think its momentum should be 10mvBsin(arcsin(3/5)). Doing the same for A with...
Hi,I m studying for college and I need to receive some info from you guys. Which books should I use to study mechanics,thermodynamics,electricity and magnetism?
I have no idea what books I should study because my own physics teacher has some pdfs in her USB and I can t borrow the USB because...
Hi,
I was looking over one of the sample examples in Halliday and Resnick, the one
about the scale in the elevator. There is something that bugs me about it, and I'd
like to know if you agree.
The example has to do with finding the reading of a scale that is measuring
someone's weight in a...
Through mechanics, potential energy is released by the controlled falling of a suspended mass. At an idling condition, a one tonne mass is allowed to slowly fall. The pushing force of that mass is used to maintain a set rpm of a flywheel. The flywheel shaft drives an electric generator.
At a...
Here is my solution to this problem. Unfortunately, I can't check it because it is not contained in the solution manual.
$$\frac{dv}{dt}=\frac{dv}{ds}\frac{ds}{dt}=v\frac{dv}{ds}$$
$$\frac{ds}{dv}=\frac{v}{v'}=\frac{v}{ge^{-kt/m}}$$
$$=\frac{\frac{m}{k}v}{\frac{gm}{k}e^{-kt/m}}$$...
Hi, my name is Kennard Callender. I am an independent scientist from Panama working on the foundations of quantum mechanics and relativity. I look forward to meeting people who desire to understand nature at its most fundamental level and who can help me polish my work.
Hello
I'd like to write my matura project on a topic of physics. But I can't really find a topic. I think I'd like to do something in the field of mechanics with reference to everyday life. The project requires an input of myself in this work, that means, i have to do something empirical and...
Wiki describes the PIGA, https://en.wikipedia.org/wiki/PIGA_accelerometer. I want to see if I have a basic intuitive understanding of how it works.
https://en.wikipedia.org/wiki/PIGA_accelerometer#/media/File:PIGA_accelerometer_1.png
Lets imagine that the device, as shown, is at rest on the...
TL;DR Summary: I am missing an algebraic step in the below described three-body problem, any help is much appreciated
Consider the following setup
where the distance between the masses are ##d##, and they exert gravitational force on each other. We want to find the angular velocity of the...
I am a retired engineer, 81 years old, self studying modern physics using Young and Freedman University Physics.
I am familiar with the wave equation y(x,t) = A cos (kx - wt) where A = amplitude, k = wave number and w (omega) = angular frequency.
in the chapter introducing quantum mechanics...
Assume the part of wheel with angle ##\phi## not is cut out, but is located next to cut out part. Turn this from right to left. Then wheel's center of mass will be higher by $$R\phi \sin(\alpha/2)$$. It allows to express potential energy. But I don't know how I can express kinetic energy in this...
I understand that after stopping of rotating I should consider second Newton's law:
m d^2r/dt^2 = k(r-r_0)
And using the law of energy conservation I can propose that energy of circular motion I (\omega)^2/2, where I = mr^2 - moment of intertia will be converted into spring's oscillation. But...
Recently I started making physics problems and I made one that I really like, but I would like some feedback from other people (how difficult it is, how enjoyable it is to solve this problem, what I could improve about it, etc). Here is the problem:
A cannon is fixed at height H relative to the...
m * g = mAl * g
V * ρ * g = VAl * ρAl * g
V * ρ * g = V * ρAl * g
ρ = ρAl
this does not work at all, because the upper ball must have a density smaller than that of seawater 1200kg/m3 or not?
Hello, simplified the Angular momentum problem that comes up when i try to solve a mass moving inward or outwards and it does not conserver the angular momentum properly. I have tried this is many software by now, or by someone else and we all have found that there is no angular momentum...
I want to create a set of planetary gears using a 3D printer and PLA material. I'm designing them with the help of Autodesk Inventor 2020 since my knowledge in this area is quite limited. The gear set consists of a ring gear, a sun gear, and 2 planet gears. The sun and the ring gear rotate in...
[Mentor Note -- Two threads on the same by the OP have been merged into one]
I'm having trouble understanding the solution my professor gave me, in particular, the accelerations of m_2 and m_1. When my professor solved for the acceleration of m_2, he used a as the acceleration but when I look...
I'm confused on how to derive the multidimensional generalization for a multivariable function. Everything makes sense here except the line,
$$
\frac{\delta S}{\delta \psi} = \frac{\partial L}{\partial \psi} - \frac{d}{dx} \frac{\partial L}{\partial(\frac{\partial \psi}{\partial x})} -...
Hello, Springer books are on sale this week so I wanted to buy some textbooks to support my studies and (eventual) future career.
I'm an undergrad (in europe) and my courses next year will be QM, GR and statistical mechanics, so I was looking for books about these topics, but any suggestion on...