Outside Definition and 459 Threads

Homework Statement http://img825.imageshack.us/img825/5992/gauss.th.png Uploaded with ImageShack.us 2. Solutions For b) - iv They say the E-field is 0 for r > c Why? Also for part c), they say the answer should be the integral from r = a to r = b. My question is, why...

Does anyone have really nice aurora where they're from. I was outside of the city at an observatory last night, doing some observing, and while they're not great for maintaining your dark sky adaptation, they sure do make some great photos. The craziest part of the aurora was...

Homework Statement +35 + -80 with only 8-bits using sign-magnitude representationHomework Equations The Attempt at a Solution Why is this possible? Allowing for one sign bit, the maximum range (in my mind) should be -63 < N < 63. I can see from my notes, however, that the limits of an 8-bit...

Q. a particle of mass m is located outside a uniform sphere of mass M at a distance R from its centre find:- a) potential energy of gravitational interaction of the particle and the sphere b)the gravitational force which sphere exerts on the particle using G=-г m/r^3 R and ф=-г...

Homework Statement The field just outside a 3.22 cm radius metal ball is 2.72×10^2N/C and points toward the ball. What charge resides on the ball? Homework Equations E = k*q/r^2 The Attempt at a Solution q = E*r^2/k q = ( 2.72*10^2 N/C )* (0.0322 m^2) / 8.99*10^9 =...

Homework Statement Say we have a warehouse with a 5 hr time constant. The outside temp is 16C at 2:00AM, and 32C at 2:00PM. The warehouse is at 24C at noon. What will the temp be at 6:00 pm? When will the temp be 27C? The Attempt at a Solution First, I set up a sine wave for the...

Imagine you are in your spacecraft , and within your observable universe there is no other body. As far as you are aware, you are stationary. If you shine a light inside your craft you will measure its speed as 300,000kps, as you also will if you shine a light outside the craft. Nothing...

We know that the laws of physics are unique to our universe, that is they only hold true in our spacetime. My question is about logic and if logic holds true outside our universe unlike the laws of physics. For example, if we say that x>y and z>x then we can conclude that z>y is true by logic...

Is there any electric field outside the region between the plates of a parallel plate capacitor? What about near the edges? Do we neglect that variation in deriving an expression for the field inside? The positive and negative charges appear only on one side of each plate so I don't think there...

Hi, this is may be trivial but i am confused anyway, i want to ask about the force we exert or calorie we spend on a treadmil is same with outside running. I mean in treadmill the running belt somehow propels us? By the way i neglect the surface effect of the treadmill.

So I friend of mine got into this interesting discussion about different kinds of plasmas in particular the various colors andhttp://en.wikipedia.org/wiki/Plasma_parameters" of various ions (*mainly magnitude of frequency and velocity equation). One interesting question we both had was about...

What do people know about this? I want to leave the US for various reasons as soon as a finish my undergrad degree, what opportunities are there for a funded Ph.D. program abroad? I plan on applying to most non-US schools, I'm mostly interested in the other Anglo-phone countries but have...

I am surprised that I don't see topics like this but anyway, I am thinking of taking math classes outside my engineering major sheet which is called foundation of mathematics it deals with sets and proofs described :"Algebra of propositions, mathematical induction, operations on sets, binary...

In other words, has the human mind merely evolved to understand the world in terms of distance and space and time? Does time exist outside of an observer?

Someone please explain me why is the magnetic field at a point outside a current carrying solenoid 0? I read many books but can't understand what they mean. I understood that the magnetic field at a point in between to adjacent coils is 0 as the 2 fields oppose each other. Why and how is it 0...

Homework Statement We have a solenoid of radius a, length L, with ends at z = +/- L/2. The problem is to use Ampere's law to show that the longitudinal magnetic induction just outside the coil is approximately B_z (\rho=a^+, z) \approx \left(\frac{2 \mu_0 N I a^2}{L^2} \right) \left(1+...

We know that color is a sensation in the brain from interpreting different wavelengths of light. Therefore, color does not actually exist in the real external universe. Why not take it a step further and say that the sensation of brightness is a human concept. Not that actual magnitude of...

Homework Statement There is a wire with current I ,charge density j, and radius R. Find the Magnetic Field outside the wire (a>r) and inside the wire (a<r). Homework Equations Biot- Savart or Amperes law I=JdotA The Attempt at a Solution Not sure how to attempt it or which...

I need to take one more course for my EE Bachelors degree in one of three specialized areas: Signal Processing, Controls, or Communications. I know all three of these are very much related, but I am finding Signal Processing by far the most fascinating field out of the three. The problem is...

I know that most physics Ph.D's end up in wall street and jobs in finance etc. And I do know of the scarce jobs within academia. And so my question is, that is getting a job elsewhere, for instance wall street, nearly a cakewalk for a physics Ph.D. or is there a similar kind of struggle there...

Hi, when a tumor is removed from a mouse that has been killed just minutes earlier, and then this tumor is cut using a scalpel, how long do cells sticking to this scalpel survive? I am asking because I just cut a tumor, then left the scalpel on the table for 10-15 minutes, and then when...

Homework Statement A thin, hollow cylinder missing its two end caps is shown to have a charge of -90nC. It has a radius of .5 cm and is 2.0 cm long. Find the charge on an \alpha particle 5.0cm away from the end of the cylinder closest to the particle. (The center of the cylinder is on the same...

Homework Statement Consider an 8mm diameter coaxial cable, which consists of a central conducting wire, and an outer cylindrical conducting braid. If a charge of +30mC is placed on the inner conductor, and a charge of -30mC is placed on the outer conducting braid, what will the electric field...

Hi, These days you often read a lot about how tough it is to succeed in Academia, how even the people from top 10 US grad schools can't find postdocs, and so on. This seems to be even more pronounced when it comes to fields like String/Mathematical Physics/HEP Theo. Is this just a US...

1. Find the electric potential inside and outside a uniformly charged sphere of radius R, and whose total charge is q. Use infinity as your reference point. Compute the gradient of V in each region and check that it yields the correct field. Sketch V(r). 2. I used the theorem that electric...

Hello, Basically my problem is trying to understand the electric field outside of a current carrying wire. My first thought is that it is zero, but now I am not sure. The boundary condition of the electric field says that the parallel component inside and out must be the same, so this means...

Homework Statement A particle in the harmonic oscillator potential is in the first excited state. What is the probability of finding this particle in the classically forbidden region? Homework Equations probability of finding particle = integral of abs[psi squared] [a,b] The Attempt...

Hi, I've have been searching for help in calculating the magnetic field strength at any given position outside a solenoid. I can use Biot-Savart's to get the field along the axis of the solenoid but how does the field vary perpendicular to the axis of the solenoid, for example. Rob

Hi Guys .. I have a question and I hope I get a good and obvious answer PLZ .. How do stars and moon look like from outside the Earth's atmosphere ? If we went out of the atmosphere of the Earth , will we see the stars in the same way as we see them from .. here ? In other words do the...

Homework Statement The title really says it all. Find the area of the region inside r=6sin(theta) but outside r=3. Homework Equations The Attempt at a Solution I first found the x values where the two curves intersect and came up with .52359877 and 2.61799388. I then...

recently I've been thinking about what's outside of space. And this thought really relies on the big bang theory. this is because in it it claims the universe is expanding so i wondered if its expanding then what's outside of it? And would it be the end of space or everything, what would exist...

Homework Statement A conducting sphere of radius 0.01 m has a charge of 1.0 × 10–9 C deposited on it. The magnitude of the electric field in N/C just outside the surface of the sphere is Homework Equations E=kq/r^2 EA=q/eo The Attempt at a Solution I tried the first equation...

Suppose one had a solid sphere just slightly larger than its Schwarzschild radius. What would the curvature of the surface look like to a local observer? Would it curve downwards, or appear flat, or curve upwards? If my brain was working a bit better today, I'd calculate it myself from the...

Find the volume inside the sphere x^{2}+y^{2}+z^{z}=16 and outside the cylinder x^{2}+y^{2}=4. Use polar coordinates. The sphere's center lies at the origin. The region of integration is the base of the cylinder, the radius 2 xy disk x^{2}+y^{2}=4 and the two parts of the sphere are given by...

Homework Statement http://img685.imageshack.us/img685/9501/10953060.png" Homework Equations The Attempt at a Solution I know you use Gauss' Law, but why wouldn't the charges outside of the shell induce a charge on the shell, which would then affect the field at P?

I've been learning GR in my sparetime, and occationally I run into a conceptual problem that stalls my progress. Here is a question that has come up. I expect that this is a stupid question, but it's really bugging me, and an explanation will help me move forward more efficiently. If we wish...

Why is the magnetic field outside a conductor zero?

Homework Statement A 200 g, 42.0-cm-diameter turntable rotates on frictionless bearings at 56.0 rpm. A 20.0 g block sits at the center of the turntable. A compressed spring shoots the block radically outward along a frictionless groove in the surface of the turntable. What is the...

I am posting this because I am sure there are plenty of other folks out there who have elderly parent's or relative's who want to use a PC, and are not all that savvy with them. When they run into problems, getting competent help can be expensive, and time consuming, not to mention...

An infinitely long cylinder has charge density lamda and has a radius R. What is E when r < R and when r > R. I know the formula for an infinite line of charge is E = (lamda) / (2 pi epsilon not * r) Thanks!

1. You've hung two very large sheets of plastic facing each other with distance d between them, as shown in the figure . By rubbing them with wool and silk, you've managed to give one sheet a uniform surface charge density n_1 = -n_o and the other a uniform surface charge density n_2 = 3n_o ...

1. How do I determine the potential in the region outside a sphere, when I have a static charge distribution outside the sphere?

Gauss' Law only figures out the the total charge enclosed by the Gaussian surface and on it, I treid this in a few cases where charges were placed only inside the surface, and my answers were correct. But, when I tried imagining how to do this if there were charges present outside...

A little background on my situation: I was a business major for 3 years before I switched to ME. As such, I've completed my school's core curriculum and have some spare time now that I'm in the ME program, being able to take only 8 - 12 hours per semester if I stay within the curriculum. So...

Pressure is defined like FORCE/SURFACE [Pa] so the outside pressure close to the Earth is atmosphere pressure (101 325 Pa) defined by the mass of air/surface.Why is the same pressure in my house? There isn't much air like in outside...Thanks for the potential answer an sorry for the bad english.

This isn't homework - just working through questions in my text. The question gives two concentrations of calcium ions inside and outside the membrane and asks to find the Nernst potential - ok no problem there. Then it asks if the calcium ions are in equilibrium if the resting potential is...

Anyone not getting snow? My forecast for tomorrow aka "Evo Alert" And I am supposed to see the doctor tomorrow and I still haven't replaced my donut tire from when I got that flat, and the stupid car is only a few inches off the ground. Turbo has been hit pretty bad, Even Kurdt in...

I'm currently a third year physics undergraduate student at the University of Toronto --which is respectable as far as Canadian schools go. My marks are decent: 3.83 GPA of almost exclusively physics and math courses. I have recently been looking carefully at the realities of working towards a...

meaning of "vanishes outside a set of finite measure" What does it mean when we say that a function vanishes outside a set of finite measure? As in the definition of the integral as a prelude to the Lebesgue integral in Royden's Real Analysis, 3rd ed. (p. 77). It said: If \phi vanishes...

Homework Statement Use double integrals to find the area inside the circle r = 2 cos(θ) and outside the circle r = 1. Homework Equations I figured this was too easy to require an graphic. If you can't picture the circles, imagine them in rectangular from: r = 2 cos(θ) ==> y2+(x-2)2=1...