Law Definition and 999 Threads

Homework Statement A potential difference V is connected across a device with resistance R, causing current i through the device. Rank the following variations according to the change in the rate at which electrical energy is converted to thermal energy due to the resistance, greatest change...

So I understand the relationship between mass x acceleration=force but all that relationship tells me is "Whatever the force is to accelerate a given mass at a specific unit of acceleration = units of force, and we just accept whatever the unit of force is. example 1/ms² x 1 kg mass = 1 N...

Recently i am reading Classical Mechanics from Gregory In section 3.3 , he provide a statement which he named " The law of mutual interaction." as follow "The law of mutual interaction" Suppose that two particles P1 and P2 interact with each other and that P2 induces an instantaneous...

A consequence of Heisenberg's Uncertainty principle is that particles energy level can fluctuate their amount of energy, e, for a short amount of time, t, as long as e x t < h/4pi (where he is = to Planck's constant). So does that not violate the law of conservation of energy?

Homework Statement q1= 5 x 10^-6C position (1;2,-1) q2= -3 x 10^-6 C position (-2,1,3) a) what is the electric force caused by q2 on q1? (vector notation) b) what is the electric field at (0,0,0) Homework Equations F = kq1q2/r^2 E= F/q The Attempt at a Solution I really don't...

Homework Statement We were given two methods to look into Newton's 2nd Law and evaluate them by looking at where sources of error may have come from. They both involved accelerating a car across a table. A plastic track was used to guide the car along a straight path to make sure it went...

There is magnetic field in B = B ##\hat z## in a region from x=0 to x=l. There is a metal rectangular wire loop with length l and width w in x- y plane with coordinates of four corners as (0,0),(0,w),(l,0),(l,w). This loop is moved with velocity v=v##\hat x##. Now according to Faraday's law...

Hey guy! I used google but it didn't help so can you guy pleas tell me how Mr.Newton explained his law please. Thank!

Hey guy! I know how Newton's first law said but i can't understand why. So can you pleas help and tell me why. Thank you!

Homework Statement Hello, this is more of a conceptual question than a concrete homework assignment question. I'm learning about Gauss's law and the Prof did an exercise on a sphere with uniform charge distribution, where he found E(r). The trick was, that E(r) was constant over the Gaussian...

From what I know, the law says that disorder increases over time. But, when a building is constructed the disordered bricks,cement etc. take form of the ordered building. Am I wrong or is this an exception?

Hello. I am reading "Introduction to Solid State Physics" by Kittel and there is a derivation in the textbook that I am understanding. This should be a fairly simple question but I am unable to see it. 1. Homework Statement In Chapter 2, it derives the Bragg law using the diffraction condition...

Hi guys, From Boyles Law, we know that Volume is inversely proportional to Pressure give that the temperature is kept. My question, if we decrease the volume, the pressure will increase due to rate of change of momentum ( we can say those two are proportional), then why can we not claim that...

Homework Statement The aim of a laboratory course was to measure the x-ray fluorescene spectra of 20 metallic samples. By comparison of the peaks in the energy spectra with known electronic transitions (e.g. ##K_α## of ##Cu##) the materials were identified. After that, Moseley's law $$...

Consider a frame S' moving with speed u along +ve x direction with respect to another frame S. Consider a body moving with speed v along +ve x direction with respect to frame S . Both frame are inertials. here,force acting in S frame on the body is $$ F\hat x=\frac {dp} {dt}\hat x,$$...

My university is now newly offer a double degree in engineering and law. I am going to major in mechanical engineering. The law degree offered is either J.D. or LLB. I am not sure about that because my university has no experience in this kind of jointly offered program with other university in...

Perhaps the title of this post is not quite correct because I could not find a way to abbreviate what I am asking. Picture a magneto circuit, where, an alternator is used to generate an AC flux into a primary coil of a ignition coil by means of a magnetic core (the primary is wrapped around the...

Hello,one thing really confuses me ,in an open circuit the value of resistance is 0 and so due to v=iR the voltage also becomes 0 but my question is how can a current flow in a circuit where there is no voltage Difference? Please help. Shafia.

Brewster's law on polarisation states that if a unpolarised light is incident at a certain angle of incidence, then part of it gets plane polarised and is reflected. What happens if the incident light itself is vertically polarised for the same brewster's angle and same wavelength of light used...

When students are first taught trigonometry in public high schools across the USA, they eventually learn about the law of sines and law of cosines. However, the law of tangents is not taught. 1. What is the law of tangents? 2. What is the usefulness of this law? 3. Why do YOU think the law...

Hi everybody, I apologize if something like this has been asked before but I have been unable to find an answer through searching. If a weight is carefully added to a moving cart then the cart should slow down due to conservation of momentum. How is it that the cart has accelerated without a...

Well, I have checked out the ones with calculus but I was just wondering if there was one without calculus I tried it but could not do it I think Fermat's principle can be used to do it but I am not being successful So, anyone please help

I WAS THINKING ABOUT A REGION OF SPACE WITH ELECTRIC FIELD ALONG POSITIVE X DIRECTION AND Varying WITH SPACE COORDINATE(x) NOW IF ONE IMAGINES A CUBE IN SPACE SUCH THAT FIELD CROSSES ITS TWO FACES AT RIGHT ANGLES ,A SIMPLE Application of...

I began reading Mehran Kardar's Statistical Physics of Particles and about halfway through the first chapter, there was a discussion on the second law of thermodynamics. He makes no mention of the old tenet that 'the total entropy in the universe must always increase' (I'll refer to this as the...

Hi all, I'm after a little guidance for I do not know what is going wrong. I understand that for Johann Bernoulli's proof of the brachistochrone problem he used refraction of light and Fermat's principle of least time. I have decided to do a project on the subject, in which I am dividing up a...

Homework Statement "Calculate the net force with the resultant angle acting on each object indicated in the diagram." The line going off to the southeast is supposed to be straight. My computer art skills aren't great. | 22 N | |_ _ _ _ _ \ ) 35 degrees \ \ 38 N 2...

Homework Statement The two forces F⃗ 1 and F⃗ 2 shown in (Figure 1) act on a 29.0-kg object on a frictionless tabletop. Suppose that F1 = 10.8 N , and F2 = 19 N . A. Determine the magnitude of the net force on the object for the diagram (a) in the figure. B.Determine the angle between the...

Then it goes on explaining how Gauss law would fail because for a very large surface, E field would be vanish with flux through it and though we can calculate div for this field it won't depend on source density. But I don't get what makes this particular function so evil that it would break...

What does it mean for the laws of physics to be reversible in time? Does it mean that for every possible physical process, the same process can happen as it would do if we "played the tape backwards" so to speak? If a particle follows a path due to some physical law, Does it mean that if we were...

Is forcing a closed system to expand (e.g. by pulling out a piston), causing it to cool, work done to the system or work done by the system? I assume it was work done to the system, but that means the first law of thermodynamics formula no longer balances if you assume an adiabatic change...

Okay...Hook's Law is stated as ''the force (F) needed to extend or compress a spring by some distance X is proportional to that distance. That is: F = kX (Wikipedia)'' And further on this topic there is a statement that ''Hooke's law for a spring is often stated under the convention that F is...

Homework Statement An infinite metal plate has a surface density of charge σL=-6μC/m² , Left side and a surface density Of load σR=+4μC/m² , in the right side. A Gaussian surface In the form of a circular cylinder, with area A 12 cm², is Located with the left side inside the plaque and a thin...

Homework Statement Homework Equations Using Loop 1, 2 and 3 The Attempt at a Solution

I'm sure I read somewhere in my physics books that non-locality is required in order to maintain the integrity of the 1st Law of Thermodynamics. Is that correct? If so, that seems to require one or more additional spatial dimensions via which the total amount of energy is maintained. What...

Homework Statement I'm not sure if this is introductory or not but here goes anyway... So we have this experiment to measure the flow rate of viscous fluids by forcing them up a measuring tube using some compressed air in a drum. The idea is to test the limits of poiseuilles law with various...

Homework Statement Two people each with a mass of 70kg are wearing in line skates and holding opposite ends of a 15m rope. One person pulls forward on the rope by moving hand over hand and gradually reeling in more of the rope. In doing so, he exerts a force of 35N (backwards) on the rope. This...

Homework Statement I have ##E(w)=w^3(e^{\beta\bar{h}w}-1)^{-1}##, where ##\beta=K_{B}T##, ##K_{B}## boltzman constantHomework Equations Need to solve ##\frac{dE(w)}{dw}=0## The Attempt at a Solution [/B] ##k=\beta\bar{h}##...

The textbook proves that ##x^a x^b = x^{a+b}## by an induction argument on b. However, is an induction argument really necessary here? Can't we just look at the LHS and note that there are a ##a## x's multiplied by ##b## x's, so there must be ##a+b## x's?

Hello, quick question here I am studying mathematical astronomy / the history of , and I have noted that by raising the average sidereal period of any planet in our solar system, to the power .666666, that you are left with the average distance of that planet from the Sun, in AU I was told...

We were asked to do an experiment where we had to prove the equation: T2=(4π2m)/Mgr Where M is the mass of the mass stack in kg (0.3kg), m is the mass of the rubber bung in kg (0.0226kg), T is the time taken for one rotation in seconds, r is the horizontal radius of rotation in meters, and g is...

According to Gauss Law, we only consider charges which are inside the surface to produce net flux. We disregard the charges outside the surface because they produce zero net flux (as the electric field lines enter the surface and leave the surface producing zero net flux) My question is, since...

Sorry if this is a stupid question, I don't fully understand entropy. Snow flakes are highly structured, they form from water vapor which has very little structure. I must be misunderstanding entropy, my interpretation of it is that isolated system must evolve into more chaotic less structured...

Homework Statement A spring (k = 500 N/m) supports a 400 g mass which is immersed in 900 g of water. The specific heat of the mass is 450 J/kg and of water is 4184 J/kg. The spring is now stretched 15 cm and, after thermal equilibrium is reached, the mass is released so it vibrates up and...

If you have a U-shaped pipe like the attached image, with more fluid in the left column than the right, then the fluid will level out basically because of Pascal's Law. Force on the fluid is exerted on every part of it in equal direction etc.. So when the fluid levels itself it flows across to...

(Kurzgesagt- In a Nutshell) says that in the Big Freeze scenario all the matter will decay in the end, how is this possible without breaking the law of convervation of energy?

Homework Statement A metallic sphere of radius a is placed concentrically with a metallic spherical shell with inner radius b and outer radius c. The sphere has a total charge of 2Q and the shell has a total charge of 3Q. (a) What is the charge distribution? Specifically, what is...

I am not sure that I fully understand even the basic aspects of the Quantum measurement and entanglement but I just came across this thought experiment and I wish to resolve it. In a setting of two entangled spin-1/2 particles, suppose that Alice applies a uniform magnetic field ##B_0## along...

Homework Statement Theres a cylinder rod inner radius a outer raidus b.we want to find electric field between a and b,like point r (or radius r) a<r<b. Homework Equations Gauss Law The Attempt at a Solution [/B]I am trying to find Q enclosed but something make me confused.I am...

Homework Statement Uniform Slab: Consider an infinite slab of charge with thickness 2a. We choose the origin inside the slab at an equal distance from both faces (so that the faces of the slab are at z = +a and z = −a). The charge density ρ inside the slab is uniform (i.e., ρ =const). Consider a...

Homework Statement The value of the line integral around the closed path in the figure is 1.79×10−5 Tm . https://session.masteringphysics.com/problemAsset/1385538/4/32-22.jpg There is I2 and I3 inside the closed loop. I2 = 12 A What is I3? Homework Equations Amphere's Law: B = Uo I(enclosed)...