Laws Definition and 1000 Threads

Hi friends, The problem is from Newton's Laws. The problem is as follows: https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-ash4/1006364_1417581381802301_666606151_n.jpg IInd law states, Force, F = dP/dt => F = d(mv)/ dt Out come, If m is constant, v is variable, F =...

Homework Statement Relavent information is provided in the picture. Trying to solve the currents, I1, I2, I3.Homework Equations I(1)+I(2)+I(3)=0The Attempt at a Solution Too messy to even show. Basically I'm having a massive trouble understanding kirchhoffs laws and this problem in particular...

I'm new to this forum, so Hi! :) I have a test on Newton's Laws of Motion, the day after tomorrow and will appreciate any kind of help on these problems. Thank you very much, and nice to meet you all. :) -------- Q1. A particle of mass m moves with constant speed v on a circular path of...

Homework Statement Figure 1 shows a box of mass m2=1.0 kg on a frictionless plane inclined at angle θ=30°. It is connected by a cord of negligible mass to a box of mass m1=3.0kg on a horizontal frictionless surface. The pulley is frictionless and massless. (a) Choose the direction of your...

Homework Statement A "Pedagogical machine" is illustrated in the attachment. All surfaces are frictionless. What force F must be applied to ##M_1## to keep ##M_3## from rising or falling? Ans. clue. For equal masses F=3Mg Homework Equations The Attempt at a Solution I would like...

Can anyone define the distinction between the laws of nature and the kinematics of nature? I am thinking that laws have more to do with forces and potentials and kinematics have more to do with velocities and reference frames but I cannot formulate a clear definition of one that does not overlap...

Basically I don't know anyone in real life that can help me with this, so I need help checking to see if my answers are correct :) PART A 7) Simplify (5x^3yz^2)^2(-3x^3y^4z) My answer: -75x^9y^6z^5 8) Simplify the problem below using positive exponents only. 8a^-2b^3c^4 18a^5b^-3c My...

Hello! I have a question that has been bothering me for some time, and I thought this would be a good place to ask. This is my first posting on PF as well, so I hope this is well placed. There are force laws for the coulomb attraction and gravity. Are there similar force laws that can be...

Hi all, I know about Kirchhoff's voltage and current laws when it comes to simple circuits with two-terminal elements and junctions/nodes of branches. However I'm curious how KVL and KCL are applicable to multi-terminal elements? Does KCL apply to any junction of branches no matter what that...

why are many fundamental laws of nature formulated in the form of differential equations?

Homework Statement Can Kirchhoff's voltage and current laws, and Ohm's law, be used when analysing circuits with constant voltage and current sources, but also diodes? I'm trying to analyse such a circuit, and I'm finding that current is flowing backwards through one of the diodes...

2) A π0 of kinetic energy 350 MeV decays in flight into 2 γ rays of equal energies. Determine the angles of the γ rays from the incident π0 direction. Not sure where I am going wrong but my answer is not correct. Energy of π0 meson E = 350 MeV Rest mass Energy of π0 meson E0 = 135...

Newton's laws, coulomb's law are all very neat but are they totally accurate? According to modern instruments which can measure up-to remarkable precision, do these laws behave perfectly? I haven't studied quantum mechanics yet but as far as I have heard it's all about probabilities ... we...

A tangential force is appliied on pully hinged at its centre of gravity. will there be any reaction force at its center?? if yes then how much? will it be same as applies force? practically it seems there would be no force at its center?? and if force is applied from the both side say P1 and...

Hi, i am very confused on how your supposed to do these two quesitons. I am currently taking a intensified g11 course during the summer, and i think the teacher is going to fast, and I am not sure how I am supposed to do this. Please help explain each question out thoroughly, also it would be...

Doesn't traditional time travel violate conservation laws? If I could in effect materialize in the past, then the universe, being an isolated system would have suddenly gained matter/energy out of nowhere! Also, the atoms that make up my body would then be in two places at once since they...

Why is "squaring" so significant when it comes to basic physical laws? Let me begin by saying I do not have a background in physics, or science for that matter! I just have an interest in things like cosmology and particle physics because I like to understand things. So my question is this...

Homework Statement Simplify this expression and express the result with only positive exponants. Homework Equations The expression: ##\left( \frac {(-49^4 \ c^{-2} \ d)^3}{14^6 \ c^{-1} \ d^2} \right)^{-1}## The Attempt at a Solution ##\left( \frac {(-49^4 \ c^{-2} \...

Homework Statement Simplify the following expression: ##\frac{(100^3)^\frac{2}{3}}{1000^\frac{1}{3}}## ÷ ##\left( \frac{-10^2}{100^\frac{1}{2}} \right)^3##Homework Equations Start with this side: ##\frac{(100^3)^\frac{2}{3}}{1000^\frac{1}{3}}##...

if relativity is true and a photon can have no time from its point of view and have time from the point of view of an observer does that then mean the universe is not the same at every point Or is there any Reason someone might know of that means the Laws of Physics and not the same every...

Hello everyone, I'm doing some practice problems for my final exam. I came across this question: «The Haber process is being used at a pressure of 76 000 mmHg at a temperature of 450°C. Gaseous ammonia is cooled and collected after its production, in order that its temperature does not...

Greeting people of Physics, Why are the laws of physics not symmetrical between left and right, future and past, and between matter and antimatter? I.e., what is the mechanism of CP violation, and what is the origin of parity violation in Weak interactions? Are there right-handed Weak...

I've just started learning about torque, and understand that tau=Fd, but wondered how this relates to F=ma. For example if there is a rod with a pivot in the middle (say a nail), when one end is pushed down, why does the other end move up? Where is the force that causes the end to move up...

Homework Statement 1) A 1000-kg Car is parked on a 10 degree slope. Determine the magnitude of the frictional force acting on the car 2) A 2000-kg car traveling at an initial speed of 10m/s skids to a stop with a constant acceleration. The coefficient of friction between the tired and the...

i) If a wall breaks when it gets hit by a cannonball, did the wall exert an equal and opposite force on the cannonball? ii) Would the force exerted by the cannonball on the wall only be the amount that was needed to break it? iii) Hypothetically, is it possible for the wall to break but...

I am wondering ? is it possible that the constants that govern the laws of physics was different during other periods of our universe history ?

I was reading in my textbook the definition of a scientific law: must be found experimentally valid over a wide range of observed phenomena. So why arent things like the theory of general relativity and the theory of evolution called the laws of evolution and the laws of relativity? Will that...

Have a homework question about power law density distributions that I could use a little help on... Given a power-law distribution, ρ(R) \propto R^{-\propto}, show that a flat rotation curve can be obtained if \propto = 2 and that solid body rotation is obtained if \propto = 0. Also, I'm...

Homework Statement Does anyone know any laws equations or any other relative information between a weather balloon and scuba diving. I need to state their relationships and how the laws and equations can be used in our daily lives. Homework Equations Henry's Law, I'm not sure what else...

Hey guys. I'm new to the forum :). I'm a high school student who takes physical sciences as one of my subject. The thing is that I've been confused about something I read on chemistry. This might sound stupid but please try and understand that this is confusing me. In the gas laws, Gay Lussac's...

I am going to explain what I am looking for, of course all the while hoping that what I am looking for actually exists, by talking about how I got comfortable with the idea of harmonic oscillators. I never quite understood why the forces on a harmonic oscillator were of the form ## F=-kx ##...

Homework Statement A train moves off from a station and accelerates uniformly for 30.0 s over a distance of 225 m. It continues with the speed acquired for another 135 s, then the driver applies the brakes and the train comes to rest with uniform retardation at the next station in a further...

So one can even have "beyond standard Thermodynamics" :biggrin: I just came across this and it seems interesting. http://arxiv.org/abs/1207.0434 Laws of thermodynamics beyond the von Neumann regime Dario Egloff, Oscar C. O. Dahlsten, Renato Renner, Vlatko Vedral (Submitted on 2 Jul 2012)...

Homework Statement I have the circuit in the figure.I have to find i1 and R Homework Equations I am thinking about applying the division of the current and any of the K's laws but I don't know where to start.Can you pleas give me a hint? The Attempt at a Solution I tried to find...

1. Which of these are possible wording of Newton's Three Laws? Pick which ones are correct. Objects always fall. An object in motion always stays in motion unless acted upon by a force. When two objects interact, they experience equal and opposite forces. What goes up, must come down. An...

Homework Statement a) Find the current through the battery and each resistor inthe circuit shown. b) What is the equivalent resistance of the resistornetwork? http://s3.amazonaws.com/answer-board-image/db89d3f298e4098e8852b10c30cb3f53.jpg Homework Equations Kirrchoff's laws...

Hello, I am quite confused about this circuit: http://tinypic.com/view.php?pic=1zvtnxf&s=6 It's quite possible, that this circuit doesn't make any sense, it was made by me, out of curiosity. I know there is a junction, but from there I just can't set up any loops which would make any...

i think a few are 1. of course gay marriage why shouldn't everyone have the right to marry who they love there is more straight marriage divorce than gay marriage 2. the same amount taxed on a person no matter how much money they make thats all i got for now tell me what you think

Homework Statement At altitude of 160 km, the density of the air is 1.5 x 10^-9 kg/m^3 also the temp at that altitude is 500 K ( that's what it says! ) What is the pressure at that altitude? Homework Equations pV = nRT and mass density of air = "rho" the 1-values are at STP...

I am looking for a proof to why we can apply kirchhoffs laws and ohm's law in the s-domain. If anyone has an intuitive explanation or possibly knows of a link explaining it that would be awesome. Thanks

Homework Statement A boy skateboards down a curved playground ramp. If we treat the boy and his skateboard as a particle of total mass m = 25:0 kg, he moves through a quarter-circle with radius R = 3:0 m. He starts from rest at point A and there is no friction. (a) Find his speed at the...

Hi everyone, Here is my version of laws of thermodynamics which I would like to share it with you and hear your feedback: Zeroth Law: More than being a law, it is a definition for temperature and it follows: Two systems are in thermal equilibrium iff (if and only if) they have the same...

The three laws are already very simple and basic, is there any way to reduce them further?

say we have closed system (box) consisting vacuum and one mechanichal clock, wound to have (potential) energy (within spring) for say ten revoluntion for second hand in the begining. now when watch is allowed to have ten revolution of second hand and then it stops at the same location at it...

Homework Statement An old rope can now safely suspend 120 kg. When the rope is tied to a beam, it hangs down with a vertical length of 12.0 m. Calculate the minimum time required for an 85 kg person starting from rest to climb the entire length of the rope without breaking it. Homework...

Homework Statement We are supposed to prove that the addition and multiplication of congruence classes for integers are associative, commutative, and distributive. Homework Equations None The Attempt at a Solution To me, it seems like this would just be trivial as all these...

Homework Statement Homework Equations ƩF=0 ƩF= m a The Attempt at a Solution Since there is no friction do I assume the objects will move? or it will remain equilibrium since m1 is 120N which is way higher than 50N.

A bird flies by pushing downwards the air below its wings with a force. According to Newton's third law, the air pushes the wings upwards. As a result, the bird is lifted. Also consider the case of a rocket. The fuel it ejects exerts an upward force and as a result, the rocket moves upwards...

This is my first time posting. I see there is a protocol for making proper posts, so I am sorry if I make any errors. Homework Statement I have a problem involving a system with an incline and three masses. A picture of the system is in the attachment labeled 15.1. I am to calculate the...

Homework Statement I am trying to prove that Maxwell's laws are consistent with special relativity if one frame is moving in the x direction with another. Homework Equations In this case, I know that \frac{\partial}{\partial x'} = \gamma \frac{\partial}{\partial x} + \frac{\gamma v}{c^2}...