The syringe' plunger is in a fully retracted position (non-vacuum state) and is then connected to the tube forming an airtight seal. Then the valve to the vacuum chamber, having 29.9 Hg of vacuum, is opened.
I am fairly, certain that the plunger in the syringe will move to its forward most...
1. If the sun is reversing polarity where the northern part of the sun is showing signs of becoming positive and the southern part of the sun is already positive and if two like polarities repel could not the sun ? break in two.
2. question If the sun has two positives end and a negative...
Suppose I have to solve for y:
x\leq 1
(x - 1)^{2} = y
So I know that (x - 1) will always be 0 or a negative, therefore I must take the negative square root of (x - 1):
-\sqrt{(x - 1)^{2}} = -\sqrt{y}
Am I to understand that this is the same as:
-1 \cdot \sqrt{(x - 1)^{2}} = -1 \cdot...
Negative Changes in Entropy??
Perhaps this is not the right forum location, but I would like to ask some of the more experienced physicists here about the notion of negative changes in entropy in the universe. According to the text I am currently reviewing by Hill, the probability that a...
Hello
I am aware of what generates the electric charge of each particle, the virtual fotons around it that the particle generates, and that when two particle interact with each other a foton is exchanged and so forth. My question is though, what generates the positive and negative charge, and...
Homework Statement
http://images.4chan.org/sci/src/1340320682704.jpg
I am to write KCL equations for this circuit. Why is it that the current flowing AWAY from Node C is written as V2(t). I thought that when a current was flowing AWAY from a node, the current would be -V2(t)...
Homework Statement I know I posted a question yesterday also, but this homework is getting on my nerves. My prof isn't the best out there. So basically the question is as follows:
http://img812.imageshack.us/img812/8130/problem6.png
Homework Equations
Not sure, I sort of answered the...
Homework Statement
Show that negative divisors of an integer, are just the negatives of the positive divisors.
The Attempt at a Solution
having an integer n and a negative divisor k, we get the positive divisor by multiplying (-1)k, thus each negative divisor of an integer, is the...
Hello,
not sure if I'm typing the question in the right place, but I encountered this question when going through Peskin (eq. 6.44, though it's not important). If p and p' are respectively the momentum of electron before and after the scattering, then q=p'-p is the momentum of photon joining...
Homework Statement
Suppose an object has a velocity v and an acceleration of a, where a is negative. The object will eventually reach a velocity of zero v = 0. How much distance will the object travel until v = 0?
Homework Equations
v = u + at
s = 0.5(u+v)t
s = ut + 0.5 at2
v2 - u2...
I get that collector current is fixed so as collector current goes up, the voltage drop across the collector resistor goes up and the collector-emitter voltage goes down. Which is why it is basically zero at saturation. But for ac it is not zero but negative when input is positive. why is this...
Hi All,
Can anyone walk me through this problem. This is from an old med school entry test.
The answer is 81 but I can't work out how the x terms cancel.
3x(3x^ -1/3)^3
Thanks in advance
John
What is the "first positive", "second positive", "first negative" systems of nitrogen
Hello,
I have been trying to catch up on spectroscopy theory, and I'm trying to get a grasp on what all the terms mean. I constantly seem the terms "first positive system", etc... coming up, and I'm not sure...
Does anyone know if I run 12 volts dc at 1 amp power for a distance of 250 feet and one wire is 12 gauge used for positive and other negative wire is 20 gauge will the smaller ground wire affect what the positive wire can carry?
John
In the Klein-Gordon equation (spin 0), the mass dependence is (only) through m^2, whereas in the Dirac equation (spin 1/2) it's through m.
Does this mean that for spin 0 particles, we can just as well describe them as having negative mass without changing any of the physics (whereas for the...
I accelerate a mass upward by 2G (2×force of gravity) over some change in height Δh_{1}, then I apply only \frac{1}{2}G over some other change in height Δh_{2}.
If, over Δh_{2}, the mass still moving upward (but accelerating downwards), am I doing positive work over Δh_{2} even though the mass...
I think this is one of those papers that will have millions of citations
http://arxiv.org/abs/1205.3807
Accelerated Expansion from Negative Λ
James B. Hartle, S. W. Hawking, Thomas Hertog
(Submitted on 16 May 2012)
Wave functions specifying a quantum state of the universe must satisfy...
Hey all,
I'm trying to solve a problem in which I have a uniaxial (uniform in two directions, different in the other) crystal with the optical axis normal to the plane of reflection. I call the permittivity parallel to the optical axis ε_par and the permittivity in the other two directions...
Ok, this one's got me stumped!
Let's take as an example the probability density function for a random variable X so that:
f(x) = \frac{4}{3x^{3}} 1≤x<2
f(x) = \frac{x}{12} 2≤x≤4
f(x) = 0
So the CDF for this variable comes out as:
F(x) = \frac{-2}{3x^{2}} 1≤x<2
F(x) =...
I was wondering about a system, specifically quantum, though classical solutions are still welcome, which was resisting all applications of Noether's Theorem, and related techniques. If a system is invariant under a switch from E→-E AND m→-m, then what are the conserved quantities (in analogy to...
Hi!
Homework Statement
1. Substituting an ansatz \Psi(x)= u(p) e^{(-i/h) xp} into the Dirac equation and using \{\gamma^i,\gamma^j\} = 2 g^{ij}, show that the Dirac equation has both positive-energy and negative-energy solutions. Which are the allowed values of energy?
2. Starting...
Hi
this is my first subject in this forum and i hope you can help
1.we have been given an assignment to analyze this non-ideal op amp with both positive and negative feedback and to be honest i don't even know where to start
i know i should post an attempt of trying to solve but honestly...
I'd like to know how do i find I2 (Negative sequence current) if I know Ia, Ib and Ic but don't know angle (in normal system_not fault)? My system's 3 phases 3 wires.
I built a clock generator using a 555 and I fed the output to a high pass filter. It works for the most part, BUT the input voltage ranges from 0 to 5V while the output is -5 to 0 V. I can't figure out why this is happening. I'm new to EE, so bear with me.
Who first assigned "negative" to electrons and "positive" to protons?
a sort of history question...
the fact that the actual flow of charge (which are electrons in metal conductors) is in the opposite direction of the "positive" current flow in circuits has always been an annoyance to me...
I just completed a problem regarding a Millikan Oil Drop Experiment. I ended up with a negative voltage in the solution.
I am just trying to understand negative voltage. Does it mean that the current will travel from - to + instead of the conventional + to -?
Hi there,
Please help :) out of school for years started studying again and finding it so hard to pick up the basics again! But am trying very hard!
Homework Statement
Simplify the expression and eliminate any negative exponents
Homework Equations
(2x^3)^-2 (3x^4)^2...
if electricity is flow of electrons and also positive and negative charges attract
then why electricity needs a conducting medium.
electrons has mass and it should just travel through vaccum
then why in vacuum electricity cann't travel
please reply!
I'm studying for an exam and I'm struggling to understand op amps, here's my problem:
I understand that for an op amp to have a controllable gain, the difference between the input terminals must be very very close to zero (and you can assume it is zero). And to do this you use negative...
Find the sum of
e^(-nt) as n = 0,1,2,3,...
Apparently it's 1/(1-e^-t)
Can't use normal geometric series formula though as if a =1, r = e?
Any ideas
Thanks :)
If resting potential is negative, then K+ ions shouldn't be passively exiting the cell. It doesn't make sense for a male that is attracted to females to leave a club full of females and go outside where there are lots of males. There are females to be had!
The reaction between sodium carbonate and calcium chloride gives the table salt and calcium carbonate. The reaction takes place immediately after mixing two solutions. Can anyone suggest me how the reaction can be slowed down?
Thank in advance
Peace
Deb
Homework Statement
The question is to find sin 2x, cos 2x, tan 2x from the given information: sin x = -\frac{3}{5}, x in Quadrant III
Homework Equations
Half Angle Identities
cos2x = cos^{2}x - sin^{2}x
sin2x = 2sinxcosx
tan2x = \frac{2tanx}{2-tan^{2}x}
The Attempt at a...
Hello,
Second term of a geometric series is 48 and the fourth term is 3... Show that one possible value for the common ratio, r, of the series is -1/4 and state the other value.
ar=48, ar^3= 3... so ar^3/ar=3/48 which simplifies to r^2 = 1/16, therefore r = 1/4
Can anyone explain where...
Homework Statement
see attachment
Homework Equations
The Attempt at a Solution
Do you see the step where they go from (1.35keq2)/a2
to 1.91keq2)/a2 ?
I can't get that step. To my mind. If you square 1.35 then take its square root, you get 1.35 not 1.91
What is the difference between decreasing acceleration, deceleration and negative acceleration? Most importantly, i want to clarify that acceleration is the rate of change of velocity over time, it Does not necessarily mean that the car velocity is increasing and that a car is speeding up when...
Homework Statement
The Clausius inequality combined with the defintion of entropy yields an inequality known as the increase of entropy principal, expressed as
Sgen ≥ 0
where Sgen is the entropy generated during a process.
Homework Equations
Sgen ≥ 0
The Attempt at a Solution...
Can the spring constant "k" be negative ?
Hi,
I found a difficulty when solving this problem from my textbook :
In the arrangement of Figure 7-11 (which is basically a standard block attached to spring resting horizontally), we gradually pull the block from x = 0 to x = +3.0 cm, where it is...
I started wondering about this after solving a problem on the exam. Here is the problem: 2 planes has a speed v1 and v2. They are flying from the airport at the same time. The difference between their landings on the same airport is t. Express the distance between the airports as functions of...
Dear all,
I'm facing a problem in performing incomplete Cholesky decomposition of sparse matrices. I use the algorithm which avoids talking square roots, given in here: http://en.wikipedia.org/wiki/Cholesky_decomposition and apply it to sparse matrices by just skipping the zeros ( no...
Consider an op-amp in which there is a DC voltage of 100mV for example applied to the non-inverting (positive) terminal of the op-amp and the negative terminal of the op-amp is connected to the output directly. Also take the voltage supplied to power the op-amp, Vcc, to be 15V and the gain, A...
Red is for + and Black is for -.
If I place red rod into positive side of battery and place black rod into negative side of battery, it displays +9V.
If my hand is touching the black rod, and the red rod is touching the ground, then it displays a negative value,
I would like to know...
I'm kind of struggling with the concept of energy. A particle in a conservative field has kinetic and potential energy (E=T+U), but I can always choose an inertial frame where the motion of the particle is zero, which means I can change the the particle's kinetic energy by just switching frames...
Probably the stupidest question I have ever asked, but is it possible to prove that the multiplication of two negatives yields a positive? Go easy on me I've asked better questions :D
BiP