Laws Definition and 1000 Threads

Homework Statement A table of mass 20kg is placed on the ground. A box of mass 3kg is placed on the table. Another box of mass 2kg is placed on the table, not in contact with the first box. Another box of mass 1 kg is placed on top of the 3kg box. The earth, table, and boxes are all at rest...

Homework Statement 1)The particle shown below is at rest, where F = 65.0 N, and θ = 33.1°. Find the magnitudes of F1 and F2. 2)Just after opening a parachute of negligible mass, a parachutist of mass 99.5 kg experiences an instantaneous upward acceleration of 1.09 m/s2. Find the force...

Homework Statement 8. A cylinder 1.00 m tall with an inside diameter of 0.120 m is used to hold propane gas (molar mass: 44.1 g.mol-1) for use in a barbeque. It is initially filled with a gas until the gauge pressure is 1.30 x 107 Pa and the temperature is 22.0⁰C. The temperature of the gas...

http://www.dailygalaxy.com/my_weblog/2010/05/do-newly-discovered-exploding-stars-point-to-new-laws-of-physics.html#more In the past decade, robotic telescopes have turned astronomers' attention to strange exploding stars that may point to new and unusual physics. An international team of...

Is my understanding correct: Charge is conserved at a vertex. So the charges of particles pointing in towards a vertex and the charges of particles pointing out must be equal. Alternatively: The sum of the charges at a vertex must be zero. So if this is correct, can someone explain the...

Homework Statement A railway engine pulls two carriages of equal mass with uniform acceleration. The tension in the coupling between the engine and the first carriage is T. Deduce the tension in the coupling between the first and second carriages. Homework Equations The Attempt at...

This month at PI there will be a 3 day workshop on the Laws of Nature. As outsiders, what can we learn? http://www.perimeterinstitute.ca/en/Events/Laws_of_Nature/Laws_of_Nature%3A_Their_Nature_and_Knowability/ Smolin and Unger have a book in the works about this (time and the laws of nature)...

Homework Statement The two blocks shown in the diagram are at rest on a horizontal surface when a force P is applied to block B. Blaocks A and B have masses 20kg and 35kg respectively. The coefficient of friction between the two blocks is 0.35 and between the horizontal surface and Block B is...

Suppose, in a thermodynamic process, an amount Q of heat is given to the gas and an amount W of work is done by it. The total energy of the gas must increase by Q-W. As a result, the entire gas together with its container may start moving (systematic motion) or the internal energy (random motion...

Hey all, here's a question from one of my homework sets, any help is greatly appreciated.Homework Statement I've included a diagram of the situation. Basically, I have to find out how long it takes the block to reach the end of the ramp, the spring is massless, and friction is a factor in this...

1. What is the weight of an astronaut during lift off, if his actual weight is 750N and the acceleration of the craft is 5g's. The way I tried to solve it: F=ma F= 75(50) But answers are not matching, as the answer should be 4500N. I think I am missing something with that has to do with...

A bike starts from rest. It covers a distance of 1km from rest to rest. If the minimum time in which the bike covers the distance is 100s, the coefficient of friction between road and tyre = ? s = (1/2)at^2 no idea how to go about it.

Thank you ZapperZ for introducing these new peer-review papers. This one is of particular interest to me. I believe I may have some insight into this issue. In the normally constructed RC circuits using discrete components, the reactions of the individual components to signal frequency...

EDIT: My apologies if I started this thread in the wrong forum! Homework Statement Z = P.Q.R + P.R Where . = AND + = OR ~ = NOTHomework Equations (Commutative Law) A+B = B+A, A.B = B.A (Associate Law) (A+B)+C = A+(B+C), (A.B).C = A.(B.C) (Distributive Law) A(B+C) = AB+AC...

around 3:00 minutes into the video neil says that all the laws of physics can be simplified into one formula, which formula is this? is it e=mc^2? the video

There is a product for balancing tires which consists of tiny polished ceramic beads that you place in the tire, one or two ounces. The claim is that as the tire accelerates the beads will move to the lightest point in the circumference of the tire, thereby balancing the tire. The claim is that...

Homework Statement A painter is statically at rest on a ladder leaning against a wall. The painter argues that the force on the painter by the ladder must be equal and opposite to the force of gravity on the painter by the Earth. Evaluate the painters argument.The Attempt at a Solution the...

Have you ever used the Ideal Gas Law, Charles' Law, Boyls' Law, or the Combined Gas Law for anything in electrical engineering?

I'm nearing the end of AP Chemistry, and in review for the big test I came across my old friend, Chemical Kinetics. Also being near the end of Precalculus, the "differential" and "integral" laws piqued my interest. Remembering that I have not taken any Calculus lessons, can someone help...

http://www.smh.com.au/world/antiabortion-bill-to-block-foetal-test-results-20100421-szqu.html" Withholding test results from patients? Publishing patient information online? Forcing procedures and propaganda on patients? Is this constitutional? I know it's not ethical, it violates both...

Homework Statement The coefficient of friction between the block of mass m1 = 3.00 kg and the surface in the figure below is μk = 0.335. The system starts from rest. What is the speed of the ball of mass m2 = 5.00 kg when it has fallen a distance h = 1.45 m? Homework Equations...

I'm a bit confused about how the Lorentz Force (as a law) stands in relation to the laws of Maxwell (independent of each other? dependent?). There are two concrete examples I can think of where they interfere with each other: 1: Lorentz Force & Faraday's Law of Induction Imagine a...

I am working on a homework assignment for my particle physics class, and it requires I understand what forces conserve what quantum numbers. As I understand it: Strong Conserves Isospin, I3 projection, s, c, b, t, Baryon number, lepton flavor E&M Conserves I3 projection, s, c, b...

i know the law (fg)'=f'g+fg' but here there is epsilon and it turns to someother sign i don't know what it says. i can't understand the transition ?

Okay, so I've been trying to wrack my brain around this concept for a while but to no avail. PV = nRT (Preal + n2*V-2a)(Vreal - nb) = nRT From these equations, it's clear that real volume is greater than ideal volume under real conditions. I understand that this is because the molecules...

A bullet of mass 20g strikes a fixed block of wood at a speed of 320 m/s. The bullet embeds itself in the block of wood, penetrating to a depth of 6.0 cm. Calculate the average net force acting on the bullet while it is being brought to rest

Homework Statement Sam, whose mass is 75 kg, straps on his skis and starts down a 50-m-high, 20 degree frictionless slope. A strong headwind exerts a horizontal force of 200 N on him as he skies. Find his speed at the bottom of the slope using Newton's Law Find his speed at the bottom...

Homework Statement To find the stiffness of a material, a block of that material is placed 30 cm under a metallic cone with 0.3 kg; the cone is free falling from rest, penetrating a distance x in the block until it stops. It is known that when the cone penetrates in the block the force of the...

Homework Statement The reaction S2O82- + 3 I-1 -> 2 SO42- + I3-1 is first order in both reactants. The following mechanism is proposed: I-1 + S2O82- -> IS2O83- IS2O83- -> 2 SO42- + I+ I+ + I-1 -> I2 I2 +I-1 -> I3-1 a) Which step is the rate determining step? b) Show that this...

Homework Statement Block A in the figure weighs 65.9N. The coefficient of static friction between the block and the surface on which it rests is 0.27. The weight w is 12.2N and the system is in equilibrium. block A is placed on a table, it is connected by a string to a wall block w is...

Homework Statement I've gone out and measured my changing weight in an elevator using a bathroom scale, taking measurements each second, with the elevator ascending 4 storeys. I am wondering if it is possible to work out the acceleration of the elevator from these results, and if so how they...

1. Which of the following relationships must be true according to the laws of series and parallel connections? The options are: I1 = I3 I3 = I4 I2 = I3 + I4 I1 = I3 + I2 V1 = V2 V3 = V4 V1 = V3 + V4 V2 = V3 + V4 V1 = V2 + V3 + V4 2. Loop and junction laws 3. By the...

http://wadvpress.org/?p=58 http://docs.dads-house.org/Statutory_Rape_Victims_Must_Pay_Child_Support.pdf Only in America could a guy get raped and have to pay the child support too.

While refreshing some thermodynamics for a personal interest in renewable energies, I drafted a reasoning that apparently leads from the 1st law to the 2nd law of thermodynamics, so that the latter, at least for ideal gases undergoing reversible processess, would seem to be just a consequence of...

I had this discussion about the differences between hypotheses, theories, and laws in my physical science class today, and I suddenly remembered the principles I had learned about in physics (e.g. Bernoulli's principle, Pauli exclusion principle). I was curious how principles fit into this whole...

Homework Statement near-field distance attenuation follows an inverse cube law (1/d^3), while in the far-field it follows inverse law (1/d). Prove mathematically how we arrive at 60dB/decade from the inverse distance cube relation and 20dB/decade from the inverse distance relation...

Hi guys I am new with physics and having a hard time wraping my head around things. A worker pulls horizontally on a rope that is attached to a 10-kg crate resting on a rough floor. The coefficients of static and kinetic friction are 0.5 and 0.3, respectively. The worker pulls with a force...

NOTE Newtons first law does NOT seem to work here, at the object does NOT keep moving at a constant speed, it actually stops. Am I missing somthing ? Wayne

Here is a copy of my notes on the motor. Basically it's just some of Newton's Law of Rotation combined with Kirchoff's Laws. Then we put the model into state space form. Could someone just please explain to me the meaning of the equations? It's been a while since I've had physics. Thanks a...

Homework Statement The 100 kg blcok in the figure takes 5.40 s to reach the floor after being released from rest. What is the mass of the block on the left? Homework Equations F=ma sf=si + (1/2)(a)(delta t) The Attempt at a Solution I know to find acceleration you use sf=si +...

Homework Statement To move a large crate across a rough floor, you push on it with a force F at an angle of 21°, below the horizontal. Find the acceleration of the crate, given that the mass of the crate is m = 28 kg, the applied force is 322 N and the coefficient of kinetic friction between...

Homework Statement Find θ and W in the figure below where w1 = 16.0 N, w2 = 25.0 N, and α = 66.5°, assuming that the arrangement is at rest. Homework Equations T_1=25/sin(alpha) F_x=-T_1cos(alpha)+T_2cos(theta) F_y=T_1sin(alpha)+T_2sin(theta)-2 The Attempt at a Solution I tried to...

Homework Statement A 1420 kg jet engine is fastened to the fuselage of a passenger jet by just three bolts (this is the usual practice). Assume that each bolt supports one-third of the load. (a) Calculate the force on each bolt as the plane waits on line for clearance to take off. (b)...

Homework Statement Suppose an aerosol can contains a residual pressure of 755mm Hg and a temperature of 25*c. What would the pressure be if the can was heated to 1155*c? Homework Equations P1xV1=P2xV2 V\proptoT The Attempt at a Solution I began by converting the 755mm Hg...

Calculate the current in each of the resistors and indictate the direction of current flow. what is the potential difference between A & B I have attached the circuit & labelled the the circuit directions using kirchhoffs laws - 1) i3 = i1+i2 FOR THE LOOP AFEBCD 2)...

I think Markopoulou and Oriti have been sniffing this out a long time. Note that Wen has heuristically linked tensor networks and AdS/CFT (strings!) in the final slide of http://dao.mit.edu/~wen/talks/09QHtop.pdf. http://arxiv.org/abs/0907.2994 Tensor network decompositions in the presence...

Hi, it is known that all bodies moving with a velocity will remain moving with a constant velocity unless a force is applied to a body. (according to Newton's laws). But I thought about this: F = Ma. But if we had a very very very very small object (hypothetically), we could virtually take...

\int_{0}^{\infty}fdx\int_{\frac{x-tx}{t}}^{\infty}dy=\int_{0}^{\infty}dx\int_{\frac{x-tx}{t}}^{\infty}fdy f is a function of x and y can i move f like i showed? can i change the order of integration ?

Homework Statement A 5.10 kg instrument is hanging by a vertical wire inside a spaceship that is blasting off at the surface of the earth. This ship starts from rest and reaches an altitude of 290 m in 10.0 s with constant acceleration. a.) Draw a free-body diagram for the instrument...

1. Homework Statement and attempted solutions Simply each of the following Boolean expressions: i) http://img69.imageshack.us/img69/4438/equa1.jpg ii) http://img69.imageshack.us/img69/9907/equa2.jpg iii)Expand the following SOP form to proper miniterms (don't forget to delete...