bodies Definition and 523 Threads

and the solutions: I am not sure why two of the bodies are at the same temperature to end with. I am pretty certain that they don't have to be - but the author of the problem set it this way for some reason I'm missing (my guess). My reasoning: Put 100 K and 300 K together for a short time...

Hi, I'm currently looking to improve my understanding (mostly conceptually) on Dynamics (such as colllisions)and Statics of Bodies that aren't perfectly rigid, while considering mass, density, thickness, shape , kinetic energy, momentum and material stiffness/strength/toughness.

Hello PhysicsForums! Here is my attempt at a solution for the problem stated above: Where m1 and m2 are the masses Where Ff1 and Ff2 are friction for each mass Where a1 and a2 is the resulting acceleration Where S is the fore of the wire (threadforce) Where FN is the normal force The answear...

Okay I’m assuming I have to use √1- v^2/c^2 multiplied by some coefficient of length but I don’t understand any of this and could really use help understanding the process and/or reference material that might point me in the right direction

One of the strange features of Quantum Mechanics is that for his formulation one needs the classical physics that actually should emerge as its macroscopic limit. All experiences with quantum objects have to be analyzed through classical "glasses". Naturally, then the question arises: where...

I’m analysing the gravitational relationships between different mass astronomical bodies and am getting sick of having to individually google and document these. Are there data sets out there that list pairs/sets of objects which includes their mass and distance from each other? Including...

Body 1 travels 48 light years from point A to point B at 82% of light speed. Body 2 leaves point A 33 years after Body 1 and travels the 48 light years to point B at 99.99995% of light speed. What I think I know: Body 1 takes 58 years to reach point B according to an earth observer. Body 1...

I have drawn three free body diagrams, one for each box and then I applied Newton's Second Law after choosing a reference frame rotated clockwise by ##\alpha##, with ##x## pointing south-east and ##y## pointing north-east and I got: ##\begin{cases}m_{1x}: -T+m_1g\sin(\alpha)+F_{fr_{12}}=m_1...

(0:00 / 0:42) photon going light-speed blender simulation I have no idea how a mathematician would translate this example into an equation. Every time I've worked with soft bodies I seem to run short of mathematicians buddies. Regardless of the mathematics of continuous object deformation, this...

Ok. So, I already worked on this problem, and get ##m_c## = 2m/3, which is correct according to the book. However, I also want to know the value of the tension (T) between rod A and B. Note: Before we start working on my modified question, I want to point out that the force exerted by the...

I think there is normal force from wall and applied force will balance each other but there is no counter force against mg.Both bodies will slip and fall. I am not sure.

##(T- m1g)-(T-m2g)= ( m)a##. I don’t know what m?

I don't even know where to begin. I assume that the masses are equal.

Question: A string spring is connected between two bodys with a rope above them. M1 = 25Kg M2 = 50KG Distance between them is 100m. I answered a bit and got to the point where the distance between the two masses are 110m ( the mass below got 10m lower and is on balance, I mean, acceleration = 0...

M1 and M2 are rigid bodies that connected. they spin freely around the Z-axis. At a certain time (we will set t=0) when the bodies are in the state described below, the bodies disconnect from each other when each of the bodies is given a speed addition in the direction of the X(V1 and V2 axis...

However I need to know whether Planck also had to assume that emitted light was quantised to make his model work? I need to teach this topic in the context of how different experiments shaped our understanding of the light model. I have found 2 sources which seem to contradict each other:(...

Hey guy, I'm having problems to understand the final part of this section. The book says we have the lagrangian from one particle (106.16), then we have some explanation and then the total lagrangian is given(106.17). For me is everything fine until the 106.16, then i couldn't get what is going...

The attachment below describes a tank, hollow pipe and two flexible (balloon like) bags forming one body of weight W_tank. My two questions are what are the downward forces acting on the submerged body in both cases.

I have a problem with a very basic ‘thought experiment’. I can’t see my mistake(s) - I’m pretty sure there must be at least one! So I’m accepting likely humiliation/embarrassment and asking if anyone can explain where I’m going wrong... The surface of a black body (BB1) is at temperature T...

The conservation of energy equation is basically GPE is converted to KE of block and KE of cylinder. To get the correct answer, the KE of the cylinder is 1/2mv^2, where m is its mass and v is the velocity of its COM (which is the centre of cylinder). However, I viewed the cylinder as rotating...

First, I calculated the acceleration of A by the slope: -0.5m / s ^ 2 in t=4/s V=Vo+at (To bodie A) V=4-4.0,5 V=2m/s With that, I was able to find the acceleration of B: 0,5m/s^2SA= 10 +4t - t^2/4 SB= t^2/4 I equaled the two, finding t = 10s so, Va=-1m/s and Vb = 5m/s --> Vb,a = 6...

"If the sizes of charged bodies are very small as compared to the distances between them, we treat them as point charges". Can you explain me the statement. And what does "sizes of charged bodies" refer here. Thanks

Is the below Displacement time graph posible? if an object is in motion at a constant velocity, is it possible for it to stop instantaneously, or does there have to be a decelaration? According to Newton's first, an object will remain in its state of constant velocity unless acted upon by...

I'm trying to understand basic principles of ancient thrown weaponry. Let's say we have something like a bar with a known inertia tensor that is thrown from one end such that it is both rotating and translating. If it strikes something along either side of its center of mass (an off-center...

Hello there.My question is:can Newtonian gravity be generalised to include not only bodies with mass but energy also?Thank you.Can my thread be moved to classical physics?

The boom is supported by a ball-and-socket joint at AA and a guy wire at BB Hey guys, I am stuck with this question in find the Tension in B and the moments around A. I have done plenty of 2d Tension questions but not a 3D one.

Given the fact that our galaxy consists mostly of dark matter (accounting for roughly 70% of its mass) we know astonishingly little about the stuff. Admittedly, if I could give you a lump of dark matter, you would propably be totally underwhelmed by the "experience". First of all, you wouldn't...

Does increase the size of the solid body increase its entropy? I was thinking about it using the Einstein model of solid. S = k*lnΩ Ω = (q+n-1)!/((q)!(n-1)!) I am not sure how this question should be answer, i think if we talk about rigid bodies, the question don't even have sense, but about...

This post is also an invitation to compose problems of the presented below type. The Lagrange–d'Alembert principle by itself is used very seldom. It is usually used to derive the Lagrange equations and that is all. But actually it is a powerful tool in nonholonomic mechanics. As an example...

The equation manipulation that shows that bodies will fall at the same rate regardless of their mass is very straight forward, because mass cancels when you set F = ma of the body equal to gravitational force using Newton's gravitational equation. I have no problem understanding that in terms of...

Hi there! I was curious if some stars, or any other large astronomical bodies, have some kind of signature which would remain constant/identifiable between phases of their lifetime (e.g., something that would identify star 'A' whether it was a low mass star or a red giant, or later on in a...

Does the expansion of the universe affect orbits? Would the orbits of the Magellanic Clouds, for example, be different if the universe were not expanding? If orbits are affected, at what scale do we first detect the effects?

Hello Can someone please tell me what is the use of poisson's ration in determinig stress cos what I know in this case we should have stress=E*strain and so now use for poison

Hi, Is it true that measurement proves the universe has inflated by 13.8 billion light years, and if so, how do we estimate the age or distance of those measurements? What's giving me pause is my assumption that the oldest light measured (furthest away) is 13.8 billion light years old, but...

The expansion of space is about 68 km/s/Mpc, or 0.00002 km/s/light year. The radius of the sun is about 700000 km. Thus, initially ignoring additional forces, the change in radius of the sun due to the expansion of space is about 1.5*10^-9 m/sec, or 5 cm/year. I assume that this expansion is...

The dimensions of the bodies given in the problem are visual. Clearly bodies a and b are cubical whereas c is not. One side of b is twice the side of a. Both a and b are submerged to the same depth but what is the depth of submersion of c? Arranging bodies (by copying and pasting a on b and c...

Hello, I've searched a bit about about the thermal radiation behavior of non-black body and I'm confused. I've read that the color is dependent only on the temperature so every thing display the same color as a black body. But at the same time I've read that materials don't always follow the...

If there are three bodies A, B, and C arranged linearly, and B is free falling towards C, will the gravitational presence of A affect the rate of free fall of B towards C?

Good afternoon, I was wondering if someone can point me out a study or perhaps a solution, to know with some assurance if a body with a certain magnitude (m) rising before the sun with a certain angular separation (a) can or cannot been seen with the naked eye. It's the heliacal phenomenon I...

Here's my attempt for the first part: For the first body, the work obtained is ##W_1 = C_P (T_1 - T_f)## while for the second body, it is ##W_2 = C_P(T_2 - T_f).## So the net work obtained is the sum of these two: ##W = W_1 + W_2 = C_P (T_1 + T_2 - 2 T_f)## and that proves the first part...

Hello all I was hoping someone could help shed some light on understanding an equation for floating bodies. I am trying to work out the distance between B and M shown in the sketch below:- I have been given the equation:- BM = I/V BM = is the distance from center of buoyancy to the meta...

I've solved this problem, I know you equal centripetal force with gravitational force, then rearrange for velocity to find T. My answer is the same as the one in the back of the book. But then I started thinking about it and don't know why they are equal to each other. Arent the forces in the...

For instance, if a stream of muons were released from a box near a massive object and traveled on a straight path slowly (at a non-relativistic velocity) away from that object, a faraway observer would notice that the particles would take longer to decay than a muon typically would in empty...

Summary: (1) Would it be possible (relatively speaking) for a spaceship to "sit" stationary in space, i.e., not in orbit around a planet; and (2) if possible, how long would it take a planet, viewable from the spaceship's window (humor me) to pass through your field of vision? Part One I'm...

Hi all, Consider the situation depicted in the illustration. Two identical 'square plates' are situated at rest, in frame S, as shown: Plate A has its thickness 'a' parallel to the x-axis and its sides 'L' parallel to the y and z axes, while plate B has its thickness parallel to the y-axis and...

I called the smallest body ##1## and the biggest ##3##. All of them are disturbed by horizontal forces. So the free body diagrams are For ##1## ##-T_1 -Fr_1 +F=10a## For ##2## ##T_1 -T_2 -Fr_2=20a## For ##3## ##T_2 -Fr_3=30a## Then, if I consider ##a=0## and I solve for ##1## I get ##T_1=30...

Do we need more force to push a body with 100kg mass than of 1kg mass in space(in vacuum)?

Let ##Q## - charge of one of conductor, ##\phi_1## --- potential of charged conductor, ##\phi_2## --- potential of uncharged conductor. For the charged conductor: \begin{equation} \phi_1 = D_{11}Q , \end{equation} for uncharged conductor: \begin{equation} \phi_2 = D_{21}Q \end{equation}

Suppose , there is a body B1(-vely charged) and body B2(+vely charged). When both are on contact, electrons move from B1 to B2 as B2 is having electron deficit. But is reverse also possible that protons move from B2 to B1 as B1 is having proton deficit.