Forces Definition and 1000 Threads

Homework Statement A chain of mass M and length L is suspended vertically with its lowest end touching a scale. The chain is released and falls onto the scale. What is the reading of the scale when a length of chain, x , has fallen? (Neglect the size of individual links.) Homework Equations...

Looking for some help with a rear brake caliper design. The rear caliper bolts to a carrier that slides onto and rotates around an axle. An torque arm (motorcycle term) or brake stay is required to prevent the caliper from rotating when the rear brake is applied. I have to figure a way to...

Homework Statement Homework Equations T = 2π√(m/k) mx'' + kx = 0 F = ma The Attempt at a Solution I don't honestly know where to start with this. I'm really out of my league in this class, and I'm trying my best to catch up with the things I didn't quite master in Dynamics and Physics... As...

So sorry to post what seems to be a well worn question. So the 4 forces of nature work by "particle exchange" ? Yes we understand the maths of "Fields" and we have the elegance of Maxwell and Newton/Einstein and these mathematical descriptions lead us to force exchange particles which can...

Homework Statement Find height (h) of the water level which can result in failure of dam by tipping it over due to water pressure at U/S of dam. Also draw the free body diagram. Density of water to be = 1000 kg/m^3 and its specific weight=62.4 lb/ft^3 Hints: The specific weight of concrete is...

Homework Statement Homework Equations Centripetal acceleration$$=\omega ^2R$$ Coriolis acceleration $$=2v_{rot}\omega $$ The Attempt at a Solution [/B] Think of the mass as lying on an incline. The forces I know are parallel to the incline are $$mgsin(\alpha), \mu N$$ Forces I know are...

Alright, I feel this may be a pretty basic question, but I have not gotten a satisfying answer yet. I'm taking Electromagnetism right now and I got to thinking: how do fields physically interact? What I mean by this is, on a subatomic level, a field can create a force on another particle or...

Why is it so that the net work done by a force on an object is equal to change in kinetic energy only and not any other form of energy like potential energy? Also is the work energy theorem valid for both conservative and non conservative forces.

Homework Statement Each one of the force vectors are surrounded with dimensions. But you're not given any angles. How do you solve for the resultant vector like that? Homework Equations Fr = F1 + F2 + F3 The Attempt at a Solution I tried taking the arctan(200/210) on the 435 N vector to...

Homework Statement Explain why the velocity at time of impact was much higher than the average velocity Explain why the actual gravitational potential energy will in reality be much higher than this Explain why increasing the time of impact would mean the rocket was less likely to get...

How do conservative forces exactly conserve mechanical energy while non conservative forces do not. Also why is potential energy defined only for conservative forces?

Let me start by saying that I'm a physics student but I have no experience with GR other than some pop-sci and some clarifications on that pop-sci from various sources, so basically I'm saying that some math is fine but please bare in mind that I have no real experience with the relevant math...

Homework Statement Hi, this is not really an academic homework but it is something I'm trying to solve for my future project. I have a background in electrical engineering hence I'm having a hard time solving the forces problem. https://dl.dropboxusercontent.com/u/43124243/Force_problem.png...

Hello Gurus, What are the forces opposing rotary motion? And how to calculate them? For eg., if we have a shaft rotating about it's own axis, are there any other forces that oppose this motion other than bearing friction, like air resistance or some other forces. And how to calculate these...

Hello Forum, I am revisiting Archimedes principle and its important consequences. I am aware that a cube (homogeneous) made of iron will always sink in water regardless of its mass. If we changed the iron cube into a different shape (cone, cylinder, prism, parallelepiped, etc.), the object...

Homework Statement Homework Equations The Attempt at a Solution I have spent the last 2 hours trying to figure out which part of the truss is compression or tension. Hopefully the second screenshot I took is correct. I tried figuring out the first few parts, just want to make sure that at...

Just wondering about energy. I find energy and fields the 2 most fascinating parts of physics. Since potential and kinetic energy are functions of gravity (and perhaps other forces I hadn't considered); are all types of energy functions of a force? Or are there also exceptions? Or unknowns...

Well First of all, I noticed tons of thread about this in the forums and tons of the same question being asked in all kind of scientific forums. I am pretty sure everyone here hates this topic, and I have got a bad headache from reading all the comments, but just clarify this to me. "Most of...

I am trying to understand what forces keep a free vortex, (i.e. a vortex ring). Its rotating particles must have a force to avoid them going out (like gravity on planets). I have read about vortices and vorticity, but get lost in equations. Is it possible to explain the force that keep the...

If an object say a cylindrical body is gripped in a frame and that frame is being rotated by some mechanism, what forces should be considered on the gripped object in order to know the necessary force required for a proper grip?

Please have a look at the diagram. The black circle represents a motor, the green circle represents the rotating shaft of the motor, and the red beam is attached to the motor's shaft. The motor spins the red beam counter clockwise in the direction of the arrows. What I need to know is how to...

Why is the weak field a force of nature.. while the higgs field is not a force of nature.. what is the signature or things to look for before a field can be considered as a force of nature?

Homework Statement I am trying to understand how forces transfer from a wheel / pulley onto a beam, and then calculating the resulting moment. The image describe the problem. The rope is in tension with force "S", the wheel/pulley can rotate freely without any friction. Homework Equations...

Homework Statement I'm having problem of the shear force at the uniformly varying load at region EF... Why the shear force isn't -26 +(-30*4/2) at E? but -26 +(-30*4/2) at F?Homework EquationsThe Attempt at a Solution as we can see the force at region F is 0. the force due to uniformly varying...

I have a mechanism that controls the movements of multiple assemblies in the X Y and Z directions. The mechanism has been built and suffers from a wobble on a fast X travel. We have a few suggested solutions but it would obviously be a good idea to get some calculation to help prove a solution...

Hi, I am trying to design an electric scooter, in a lot of ways similar to link below: http://www.letskickscoot.com/home/articles/scooter_stance.cfmFor an all electric vehicle , I am guessing stance 1 would be similar to braking, and stance 2 would be for an accelerating vehicle's frame of...

Homework Statement (http://imagemap-generator.dariodomi.de/uploads/160725_010743_e42ea59f2569dfbV.png ) Homework Equations No equations or anything. Just need a visual concept understanding (11U Physics) The Attempt at a Solution The solutions say that all compasses should point east... So...

If I have two large cunducting bars (not the same size) that are separated by a distance D but connected with another conductor in between creating a "U" shape and apply a large current through it, how can I calculate the magnetic forces between the two large ends of the "U" shape? I have...

Homework Statement I couldn't understand why the forces act on section Bc of steel rod is 715-325 = 390kN ?Homework EquationsThe Attempt at a Solution Since there's also 215kN to the right in the rod, so forces act on section BC should be 715-325 +215 =605kN ?

Let's say I have multiple spin systems (atoms in a protein) in a solution of water and the spin systems are all producing a magnetic field \mathrm{B_{loc}} that affects nearby spin systems. Will the fluctuation-dispersion theorem apply to the force generated by a spin's magnetic field...

Homework Statement A 0.145 kg baseball traveling at 35.0 m/s strikes a catcher's mitt which, in bringing the ball to rest, recoils backwards 0.11 m. What was the average force applied by the ball on the glove Homework Equations Fnet=ma or F=ma The Attempt at a Solution I am honestly so lost...

Physicists believe at one time there was only one force. As the BB cooled the four forces we know today are derived from that one force. Why must the four forces all be equal?

Homework Statement Find the relation between the mass of block 1 and the mass of block 2. Assume that the pullies are massless and frictionless and that the rope is inelastic. All masses are unknown. Possible answers: mblock2 = mblock1[/B] mblock2 > mblock1...

Homework Statement A loaded barge has a mass of 1.5exponent6 kg and its traveling at 3 metres per second. If a tugboat applies an opposing force of 1.2exponent4 N for 10s What is it final velocity? How long does it take to stop Homework Equations F = ma F = m(v-u)/tThe Attempt at a Solution

Homework Statement An 85 kg tobbogan that was originally accelerating at 3.0 m/s2 on frictionless snow hits a bare patch of concrete that exerts a force of friction on the sled of 180 N, what will the new acceleration be? Homework Equations F=maThe Attempt at a Solution Ok so this was...

Homework Statement A block is at rest on a ramp on a table with no friction between the surfaces. The ramp has an incline of 30 degrees. The mass of the block is 4kg, and the mass of the wedge is 6kg. What magnitude force can be applied to the opposite side of the ramp such that both the ramp...

3 forces, 5N,6N and 7N act on a particle which remains in a state of equilibrium. What is the angle between the 5N and 6N force?

I am trying to calculate the forces between a simple sphere neodymium magnet on other iron surfaces and magnets. I did a lot of research but still not sure what equation to use or how to apply them. I found the following equations here (https://en.wikipedia.org/wiki/Force_between_magnets) F =...

This question might be a stretch, but I was just reading about inter- and intra-molecular forces. And I found that "Intermolecular forces (IMFs) are forces of attraction or repulsion which act between neighboring particles (atoms, molecules, or ions)"...

for my own intressest i thought of a way to look i a potato could survive a 100 metre drop. my hypothesis was abviously no not it will be potato salad when it hits the ground. but my calculations turned against me as far as i know. here are they average potato weight: 0,15 kg height: 100m i...

Hey all, I'm don't have the firmest grasp on physics and a little help would be much appreciated! So two questions: 1)a physics student watching a tennis match states, "while the ball is in contact with the racquet, the racquet exerts a larger force on the ball than the ball does on the...

Homework Statement A wheel moves to the rigth and rotates like a wheel of a bike. There are 2 bodies: - the wheel (red circle) + 2 red walls - the black arm The ground is fixed. The black arm can rotate around the red axis. The red axis is fixed to the wheel. There is no friction. The...

Homework Statement i don't understand the 8/BD = x/EB Can anyone explain about it? There's no point E in the diagram... Homework EquationsThe Attempt at a Solution

1.) from the calculation of F(AD), the force should point towards A,right? (red arrow) but, in the calculation of F(AB), the (1/sqrt rt2)(48.08) should be positive,right? (which is pointing towards LEFT)? 2. Homework Equations The Attempt at a Solution this involve the resolution of forces...

Homework Statement While reading course lecture at ocw.mit i have stumpled upon such an equation $$\dot H_O = \sum_{i=1}^n (\dot r_i \times m_i v_i) + \sum_{i=1}^n (r_i \times m_i \dot v_i) = 0 + \sum_{i=1}^n (r_i \times (F_i + \sum_{j=1, j\ne i}f_{ij} )) = \sum_{i=1}^n (r_i \times Fi) +...

Homework Statement The problem is shown in the image attached. Homework Equations ∑F = -235i -Fi +Tcos25i + Tsin25j +210cos25i +210sin25j Moment = r x F[/B] The Attempt at a Solution I have tried various things. I tried summing all the moments and then setting that equal to zero to find T. I...

Homework Statement A 2.34-kg cart on a long, level, low-friction track is heading for a small electric fan at 0.24 m/s . The fan, which was initially off, is turned on. As the fan speeds up, the magnitude of the force it exerts on the cart is given by at^2, where a = 0.0200 N/s2. A) What is...

I want to be able to build or find a mechanical device that can apply very low force/pressure to a material. I have considered using a stepping motor with a flat needle tip but I can't think of a way to make this delicate enough to not destroy my sample. I am wanting to apply forces in the range...

Homework Statement Two blocks are connected by a massless string that passes over a frictionless pulley. The coefficient of static friction between m1 and the table is 0.45. The coefficient of kinetic friction is 0.35. Mass m1 is 45kg and mass m2 is 12kg. Determine tension in the string. ***I...

Homework Statement from the notes , the author stated that force has the formula of ρ(L^2)(v^2) and also = ρ(L^3) i think there's something wrong with the ρ(L^3) Homework EquationsThe Attempt at a Solution IMO , ρ(L^2)(v^2) can also be written as ρ(L^4)(T^2) , so Force is proportional to...