bodies Definition and 523 Threads

The only formulas for forces due to a magnetic field have to do with a charged body. How can you calculate the force acting on an uncharged body? And if there is no force, why can you pick up a neutral paper clip with a magnet?

Say we have 2 bodies of m1 , m2 . The distance between them is a) r1 Ma=m1+m2 b) r2>r1 Mb=m1 +m2 In each case the mass was measured by an inertial observer . Is it true that Ma<Mb I saw this kind of thinking in measuring the energy neccesar to separate a nucleon from a...

Homework Statement A person in a hot air balloon that is rising accidentally drops a can of paint from the balloon. The balloon is moving up at a constant velocity of 4m/s, the distance to the ground is at the moment 4m. Find the time it takes for the can to drop to the ground. Homework...

Say I have two bodies, idealized as points with mass, in Galilean spacetime A^4. When thinking about the 2-body problem (just two bodies with interaction forces in the entire universe), one usually goes from the 3-dim. to the 2-dimensional problem using some special idea. I read the following...

Homework Statement Im having real trouble with drawing diagrams for virtual work. Can someone please, please help me! We were asked, in the diagram i posted, to find 1)vertical reaction at F, 2) all reactions at A, 3) bending moment and shear force at B using virtual work. i think i...

Can the distance between two bodies be calculated to prove they are gravitationally bound? Use two bodies with known mass.

Homework Statement a stone is dropped from rest into a hole. the speed of sound is 343 m/s in air. the sound of the stone striking bottom is heard 1.5s after the stone is dropped, how deep is the hole? Homework Equations kinematics equations The Attempt at a Solution not a...

Homework Statement A ball is dropped from rest from the top of a cliff that is 24 m high. From ground level a second ball is thrown straight up at the same instand theat the first ball is fropped. The initial speed of the second ball is the same as that with which the fist ball hits the...

Experiment Help! Homework Statement We were given this experiment in which we have to investigate the motion of a freely falling body on a fictitious planet. 2. Things we have to do (1) the value of the acceleration due to gravity on the planet, (sucessfully did it) (2) how the distance...

I need a formula(s)! I have a vehicle(semi) traveling on a 2% downgrade with a begnining speed of 60mph, no acceleration or braking on the downgrade. Adj "f" is .73 if that is needed. I need to be able to calculate the vehicles increase in speed in both time and distance increments. Doesn't...

Homework Statement It is possible to calculate the velocity of falling bodies (ignoring air resistance of course) using a gravitational acceleration constant. Assume: You don't know what the resistance is. The object started at rest. You DO know there is downwards motion. You don't...

It is possible to calculate the velocity of falling bodies (ignoring air resistance of course) using a gravitational acceleration constant. If there is some other resistance, other than air, is it reasonable to simply reduce the acceleration by some amount to account for that resistance, if...

The floor is smooth. Y and Z are in contact. The mass of the balls are m,m and 2m as stated. Assume all collision is elastic, what are the velocity of the three balls after all collisions?? Now, Y and Z are reversed in position. At the time of collision, what would happen for the three...

If I have two rubber coated kevlar balls, one is filled with air and the other has a gas like helium in it, if submerged underwater, would the ball with helium be harder to keep underwater than the air filled ball would be, or would they be equal in their buoyancy? Also is helium easier to...

Two indentical spheres with radius 15cm and mass 100kg are 6mm apart from echother in space. My problem is to find how long it will take before gravitational attraction will cause the two spheres to come together? What I have found out so far is: I have the gravitational force Fg= 7,12*10^-6...

It is known that radius of black hole is 2GM/c^2. And second radius is 3GM/c^2. (light ray at the second radius is not eaten but it circulate around black hole.) But, let us assume that we have body which moves almost with speed of light. 1. Are these two radiuses the same or approximately...

"Proper" accelerations and rigid bodies. In Special Relativity, the term "proper" in front of a property means, as I understand it, the value of that property as measured by an observer with test equipment at rest relative to the object being measured. Thus "proper length" is the length...

This is not homework, so I think this is the right forum. I am trying to write a program that simulates the heat transfer between, say two cubes of different volumes, heat capacities and thermal resistances. I know Newton's law of cooling just works dandy for say an object cooling in a fixed...

Hi all - I wonder if you could settle a dispute that's happening at a non-science forum? The maths itself seems complex, but the principle will be very familiar. Two bodies are identical in every respect, except for mass (e.g. a solid steel ball and a hollow steel ball of the same dimensions)...

further to earlier question on whether soul exists...I have been plagued by poltergeist like happenings since I was a kid. Either some dead person wishes to talk to me soooo badly that I'm being stalked by a ghostie...l.o.l...or my mind gets miffed and moves things around so that I notice it...

Bodies The Exhibition, has anyone ever visited that exhibition? It's coming to Amsterdam in a few weeks time http://www.bodiesamsterdam.nl/ and I'm pretty excited to be able to see the anatomy of real bodies, though it must be a really strange experience with the fact that you are looking at an...

My problem is to find the force needed to give the system of bodies a velocity of 30 ft/s after moving 20 ft. from rest. Can anyone help me with this? All i have done is found EFx and EFy for the 50lb. force.

I am doing an extra problem from my textbook as review and I am stumped. An Earth based observer sees to spaceships approaching Earth in the same direction. Spaceship A is traveling at 0.500c and Spaceship B is traveling at 0.800c. How fast is spaceship A traveleing as viewed by an observer...

Hello , I've come across a phrase that i don't understand while doing an exercise in this chapter . What's the meaning of a 'uniform paper collar' Please explain to me =) Cheers mate

I'm new to this, so I'm not exactly how to go about looking for this. It can usually lead me to articles that are over my head. I'd just like to know where to go about to understand how the following systems work. Immediate Energy (ATP-CP System) - Phosphagen System Short-Term Energy...

Hey everyone. I am working on a planetary simulation model and am having a bit of trouble with the math. Given the volume and density of a particular planetary body, how do I calculate the mass? Once I have the mass, how do I calculate the orbital distance of a satellite body to said panetary...

Well, this is my first post--hopefully I'm posting in the correct forum... I'm developing a space simulator computer application in which a rigid body's motion is calculated using its linear momentum and rotational momentum. I'm simulating multiple bodies attached together (for example, a...

Hi all! I am having trouble understanding how to create a simulation of a spinning rigid body. For each axis x, y, and z I have an angle and an angular velocity. To rotate the object each axis is rotated independently - first the rotation about the x-axis followed by the rotation about...

consider a yo-yo consisting of two cylinders of radius R1, (combined) mass M1, glued to another smaller cylinder of radius R2, mass M2. find the final velocity after falling a height h using Newton's second law. assume the string is vertical. the inner radius R2 is R0, the outer radius R1 is...

Well here's what I've done. I think I've missed the mark big time with this one... MI = 2/3 Ma^2 = 2/3 m(2a)^2 = 14/3 ma^2 Initial Energy = 0 + mgh KE + PE Energy Just Before Impact = ((1/2 Iw^2)/-KE) + 0/PE By Energy Conservation 1/2 Iw^2 =...

can anyone pls explain to me what is sliding and rolling of a let say a wheel??I'm really confuse about it thanx

This is a question out of utter ignorance: which bodies of UN are involved in authorizing a war? what i am trying to figure out is which are NOT involved. Thanks in advance. sorry if this is not in appropriate section, please move it if i posted in a wrong place :redface:

The motor of a table saw is rotating at 3450 rev/min. A pulley attached to the motor shaft drives a second pulley of half the diameter by means of a V-belt. A circular saw blade of diameter 0.208 m is mounted on the same rotating shaft as the second pulley. PART A: The operator is careless and...

Question: "An airplane engine delivers 1.5x10^6 W at an angular velocity of 2400 rev/min." A) Compute torque developed B) If a drum of negligible mass, .5m in diameter, were attached to the motor shaft, and the power output of the engine were used to raise a weight hanging from a rope...

Question: "A block of mass m1 = 1.87 kg and a block of mass m2 = 5.84 kg are connected by a massless string over a pulley in the shape of a solid disk having radius R = 0.180m and mass M = 12.7 kg. These blocks are allowed to move on a fixed block-wedge of angle 31.4 degrees as in the figure...

Hi all..new to the forums.. I've got this homework that's been annoying the hell out of me..spent ages trying to do it, but I can't get it. The problem is attached. Any help is much appreciated, cheers.

I really really hope that this is not true. I saw the video on the ABC evening news and it looked very real. Stephen Dupont an embedded Austrailian journalist shot the film. This is definitely no way to win friends and influence people.:mad...

If someone could please help me with the following question I would greatly appreciate it. An object falls a distance h from rest. If it travels 0.5h in the last 1.00s, find the time and the height of its fall. Ok, so for the second half that the object is falling, the velocity is 0.5h...

Ok guys, here is a question I have about freely falling bodies. I did do the questions but my answer just doesn't seem right to me, I don't think I went about it the right way. I will show what I did below the question: Determined to test the law of gravity for himself, a student walks off a...

Hey all - I have tried and tried to work this problem but I guess I am missing something (I can submit my answer several times to see if I am right and I have been wrong every time) - Here is the problem - A pellet gun is fired straight downward from the edge of a cliff that is 13 m...

I am so close to figuring this problem out, but I just can't quite get it. Here's the problem: At the instant the traffic light turns green, a car that has been waiting at an intersection starts ahead with a constant acceleration of 2.80 m/s^2. At the same instant a truck, traveling with a...

Does anyone know the name of the law that says that if 2 bodies of different sizes are orbiting each other, the smaller one will break up if its a certain size to the other one?

Is string theory the (more-or-less) only way of dealing with 'extended bodies' in a theory like QFT? Or does it only deal with very specific actions, or ones representing 'particles' with special dimensionalities (e.g 1+1 only)? If it is general, is all the commonly-stated phenomenology (11...

Hello everyone, Its good to FINALLY be back! :biggrin: I was wondering why the path of the planets in our solar system is elliptical and not circular? ~Kitty

yea...i'm having trouble today with my HW lol a sign weighing 400 N is suspended at the end of a uniform rod 4.00 m weighing 500 N. what is the tension in the support cable if it makes an angle 40 with the rod? now I'm curious i don't think Tclockwise = Tcounterclockwise comes into play...

I heard that each our bodies have on average a billion of shakespears body's atoms in them (A short history of nearly everything, Bill Bryson). Is there any truth in this, does that mean we have on average a billion of every persons atoms that has ever lived?

Is it possible to build a logical argument on the following line? 1) The force of gravity can only be observed between two or more bodies. 2) The claim that a single body has a gravitational field is purely theoretical; it cannot be observed. 3) If the only demonstrable gravity force is a...

Is there a commonly used single term that describes a star and all of its associated bodies including its planets, asteroids, comets, Kuiper Belt and Oort Cloud? If not, what is the most acceptable and shortest way of describing this structure?

Two bodies are separated in space through 5 light years.Suppose if one body is destroyed by some explosion .How long will the gravitational force act on other body.Whether it will affect only after 5 years?

Well, I've heard about some people who can let electricity flows through their bodies without any serious damage. Is there any sciebtific reason or theory for this? Is that the resistance f them 0 or nearly so? What do you think?