bodies Definition and 523 Threads

Is it correct to assume that two objects, with different masses, dropped from the same height at the same time will fall at the same rate until one of the objects reaches its terminal velocity? What are the applicable equation(s) used to calculate this?

Hi everyone, Im currently following an example of this paper: http://ocw.mit.edu/courses/aeronautics-and-astronautics/16-07-dynamics-fall-2009/lecture-notes/MIT16_07F09_Lec18.pdf And have reached a standstill on page 5. I am trying to plot the pseudo potential of the two bodies. I have...

The problem is: Having three bodies with thermal capacities (C) as sources of heat to a heat machine, what is the maximum work I can extract from this system, given that the bodies are at temperatures T3, T2 and T1 (T3>T2>T1), leaving them at an equal final temperature? I tackled this...

What I know: L = T - V V = e^(x1-x2) + e^(x2-x3) for n = 3 and a mass = 1 What I believe: T = .5Ʃ (x'_i)^2 from 1 to n So let's say you have three bodys that can just be considered pints masses of 1 and on the same line: x1 x2 x3 They have an...

Homework Statement The attachment shows a simple diagram of a system consisting of a Sphere(uniform) and and rod(uniform) in equilibrium. The rod is in rough contact with the sphere and hence there would be friction (acting vertically at the point of contact of the two objects). Both...

According to GR, the inertia of bodies is greater near masses. - https://en.wikisource.org/wiki/Geometry_and_Experience Has this been tested? I did not find a clear answer, the gravity tests seem to be testing other things. Can it be tested? Intuitively I think that it should be possible...

In a class at OCW 8.01 Professor Walter Lewin said... "...there are very prestigious physicists who even nowadays do very fancy experiments and they try to demonstrate that the time for an apple to fall does depend on its mass even though it probably is only very small, if it's true but they...

If you drop your shoe and a coin side by side, they hit the ground at the same time. Why doesn't the shoe get there first, since gravity is pulling harder on it?

Hi guys, my first post here :) lately I've been trying to understand how orbiting bodies (i.e. galileian moon of Jupiter) have arranged themselves in resonance the 1:1 resonance is pretty straightforward to understand. but more complex relations like the one I cited above, how do they...

How do we say(or prove) that when two bodies are moving together , they can be considered as one system? Suppose we have two blocks of wood kept on a friction less surface side by side and you apply a force on anyone of them. I suppose from left to right, then the force equations for each...

This may seem like a pretty broad question, but ill try and narrow it down the best I can. Lets say, Me, or a insect, drink some Deuteriuim oxide (under the leathal dose). How does it(d20, deuterium oxide)) interact without bodies, and what does it do to our bodies compared to regular...

Homework Statement P and Q are points 162m apart. A body leaves P with initial speed 5m/s and travels towards Q with uniform acceleration 3m/s^2. At the same instant another body leaves Q and travels towards P with initial speed of 7m/s and uniform acceleration 2m/a^2. After how many...

Homework Statement It's basically the classic problem I've seen here a lot. There are two bodies, both with equal heat capacity (C_P), one at temperature T_1 and the other at T_2. They exchange heat using an infinitesimal-reversible Carnot Engine, which will work until thermal equilibrium is...

The underlined red part: I don't particularly understand where they got this from? The yellow highlight: Why are they finding the vertical distance, instead of the perpendicular distance?

Homework Statement A single-scoop ice cream cone is a composite body made from a single scoop of ice cream placed into a cone. Assume that the scoop of ice cream is a sphere with radius r = 3.65 cm that is placed into a 9.90 cm tall cone. The interior height of the cone is 9.00 cm. The cone...

Homework Statement If you triple the distance between two objects the gravitational force will... A. Increase by the factor of 3 B. decrease by a factor of 3 C. Decrease by a factor of 6 D. Increase by a factor of 9 E. decrease by a factor of 9 Homework Equations The Attempt...

Wheeee! More confusing thread titles! Here, let me elaborate: What I intend to do here is figure out a way to roughly model the results of planetary (or larger) bodies impacting, or a planetary (or larger) sized body being impacted by a smaller body that is moving with enough relative...

Truck and car collide in one dimension. Assume same velocity. I see this as having 4 forces, two on each body. Each vehicle exerts its own force on the other. The truck exerts a force on car and vice versa. In addition, the truck's exertion of force on the car is reacted to via Newton's third...

Homework Statement Consider a system comprising two extended bodies, which have masses M1 and M2 and centers of mass at R1 and R2. Prove that the CM of the whole system is at [M1R1+M2R2] / [M1+M2 ] Homework Equations Definition of CM The Attempt at a Solution First I...

Hi, In a demonstration that was shown in class, two paper cups were dropped from different heights. The first was dropped from two meters and the other was dropped from one meter. Both landed on the ground at the same time. Why is this so? Would it be reasonable to say that if I dropped one...

I was recently thinking about potential energy and I came to two conclusions which contradict each other- 1)When a body is falling from a height, the force of gravity is acting on it in the downwards direction. There is displacement in the downwards direction. So as the force and the...

Is shown like this in my book: Consider a rotating body with an angular acceleration α. There must be a tangential force component if it is rotating: For a general point on the body we can write: Ftan = mi * ai = mi * ri * α (1) Multiply by ri and sum up you...

Why does the different in temperature between 2 body determine the rate of heat transfer? Why does the temperature gradient decrease as it reaches thermal equilibrium/fixed point of a substance? Apart from using the equation Rate of heat transfer = kA (Difference in temperature) / d How...

I'm trying to calculate the rotation of a rigid body due to a force applied to a single point on the body. This application is for 3D game programming. I understand how to find the axis of rotation by calculating the cross product of the point of intersection & the vector between the center of...

When considering the case of two or more point masses colliding in a 2 dimensional plane, is there any way to determine the final state completely from the initial conditions? if not is it not a blow to the deterministic ways of classical physics...

Homework Statement Actually, this is not truly a homework, I'm just ineterested in how to solve problems, like the one below. So, we have two conductive spheres, at a distance R from each other, the radii are r1 and r2 (r1 and r2 are comperable in size, while R is significantly larger than...

Starting at BB everything moves outwards with linear momentum so unless the BB event was rotating where does the angular momentum come from, the Earth rotates, it orbits the sun, the galaxy is rotating and the sun orbiting within it. So it seems that angular momentum is the norm for bodies...

The direction of rotating bodies about a fixed axis. I am confused on how you should regard the the direction of mg sin x, the angular acceleration and the force exerted on the body by the axis, perpendicular to OG ( where O is the fixed axis location and G is the centre of mass of the body)...

-See attached diagram - A uniform disc of mass m and radius a is free to rotate in a vertical plane about a fixed smooth horizontal axis, the axis passes through the mp A of the radius of the disc. - It then asks you to dervie equations of motion for when AO makes an angle pheta with the...

I'm taking dynamics of rigid bodies, I'm having some trouble with impulse and momentum. Basically ,I know that angular momentum abt. a point ,is the linear momentum multilied by the moment arm . BUT ,I'm not feeling at all comfortable appliying it For example , When is H abt. a pt. p =...

Well, am an Alevel student... Edexcel.. I just find quantum physics a really really confusing topic.. My question is particularly in black bodies. If we consider the sun as a black body, where did the radiations of the sun initially come from. I don't mean the emitted radiation we see, i mean...

Homework Statement The same force that gives the standard 1 kg mass an acceleration of 1.00 m/s2 acts first on body A, producing an acceleration of 0.640 m/s2, and then on body B, producing an acceleration of 0.359 m/s2. Find the acceleration produced when A and B are attached and the same...

Car A has twice the mass of Car B but only half as much Ek (Kinetic Energy). When both cars increase their speed by 6.00m/s their resulting Ek's are equal What were the initial speeds of both cars? ANS 1= 4.24m/s ANS 2= 2.12 m/sKe=1/2mV^2 m(a)=2m(b) Ek(a)=1/2Ek(b)...

I'm sure that this is not a new question, but it is one that has been puzzling me for a long time. In our universe, the large massive bodies are all moving relative to one another at low velocities relative to the speed of light (aside from the ultra large-scale systematic motion associated...

Homework Statement The uniform 3.6m pole is hinged to the truck bed and released from the vertical position as the truck starts from rest with than acceleration of 0.9m/s^2. If the acceleration remains constant during the motion of the pole, calculate the angular velocity of the pole as it...

What happens to bodies of mass as they approach and get near this value? If they don't actually reach the criteria, will their properties be vastly different from bodies that do reach the criteria? Will it expand instead of maintain it's radius? I'm also wondering how much energy it takes...

"Relativistic Mass" thought exercise with approaching bodies I understand that the concept of 'relativistic mass' is somewhat controversial, but for reasons that are unclear to me. Nevertheless, I humbly pose the following thought exercise/inquiry: For starters, I understand the formula for...

Homework Statement The central moments of inertia of the gears A and B as shown are 10 kg.m2 and 20 kg.m2, respectively. If the mass of the block C is mC = 50 kg and the system is released from rest, determine alpha A of the gear A fig is attachedHomework Equations The Attempt at a Solution...

Does a particle placed midway between 2 massive bodies experience weightlessness? Is gravity zero at this point or we just have 2 equal and opposite forces resulting in net acceleration of zero? In other words, if we pulled or pushed a particle in opposite directions but with equal force, the...

I only just started learning about special relativity in my physics class, and I have been running into a problem that none of my teachers have satisfactorily explained. Objects X and Y are moving relative to one another at some significant fraction of the speed of light, where ɣ is the...

Homework Statement If two bodies one light and other heavy have equal kinetic energies, which one has a greater momentum. Homework Equations The Attempt at a Solution the way i am solving this problem is , i am assigning any arbitrary values to both masses and velocity of anyone...

My question is quite a simple one, but one that is confusing me quite a bit. I was think why a ship needs an anchor? This sounds silly but this is why I ask. When you but a ball in the middled of water for example and you are a meter away and create waves in the water the ball just move up and...

Homework Statement An engine is suddenly coupled to a rotating drum by a friction clutch. the moment of inertia of the engine is equivalent to a mass of 40kg acting with a radius of gyration of 111mm. the drum has a mass of 10kg and a radius of gyration of 100mm. the initial velocity of the...

Homework Statement Problem 15.18: I've defined the positive J (fixed) axis along the pole pointing upwards and the positive X (fixed) axis going to the right, with both centered at the point of contact between the hoop and the pole, which I will refer to as point O. The rotating axes...

I'm a year 12 physics student and I have a keen interest in the inner workings of a magnet. I know that magnetic fields are created by the motion of charged bodies. 1. Is this somehow related to the how magnets create their fields, within their structure at an atomic level? I've heard that...

Homework Statement The uniform 3.6m pole is hinged to the truck bed and is released from the vertical position as the truck starts from rest with an acceleration of 0.9m/s^2. If the acceleration remains constant during the motion of the pole as it reaches the horizontal position what is the...

My lec notes only specifies animal hippocampus, eg dog has this and unclear about humans. Humans do have this right, and it is a post mortem diagnostic method of rabies in humans right?

Hi all, This is a kind of idiotic question. The presence of heavenly bodies in cosmos creates curvature in cosmos according to GR and the space has a kind of fluid like nature. I was wondering if the motion of stars through space creates trails. It sure doesnot. My question is why not?

Calculate the support reactions at B and E for the 9m length beam shown below. I have the answers at 4.71KN and 1.79KN but it is old work that i am revising and i can't remember how i got to them. One of the supports not being at the end is throwing me off. If anyone could show a rough working...

I am making an n-body simulator, but I'm stuck. How can I find the components of the Force acting between two bodies such as the Earth and the Sun. I know it's- F * Cos(theta) and F * Sin(theta) but if I don't know the angle how can I find the components? I'm using the diagram on this...