Short Definition and 505 Threads

Homework Statement Pic A, what's the I2? Pic B, what's the current across a-b ? Homework Equations V = I*R Voltage in series is different, the current is the same Current in parallel is different, the voltage is the same The Attempt at a Solution from Pic A, I found that I1 = 1A, I3 = 1A...

I am currently working on my high school's upcoming production of Beauty and the Beast. In the musical, there is a rose which loses petals at specific moments in the script that represent the castle's inhabitants slowly becoming less human. I figured that one of the best ways to do this remotely...

This isn't homework, it's a proof left to the reader as I self study Munkre's 'Elements of Algebraic Topology' Prove that if the sequence ##A_1 --> A_2 --> A_3 --> A_4 --> A_5## is exact Then so is the induced sequence: ##0 --> cok(a_1) --> A_3 --> ker(a_4) --> 0## where ##a_1## and ##a_4##...

its a simple circuit one branch has a resistor and its in parallel with a short i understand that the short branch has no resistance other than the wire itself which means it has super small resistance and by ohm's law I = V/R where the voltage is divided by a super small value means the...

Homework Statement [/B] I'm going exercises and I understand that if the circuit is short circuited that R=10 ohm is 0. (Trying to find Thevelin R in all of these btw) But then I ran across this one where when it's short circuited, isc is found using the current divider principle and it's...

\documentclass[12pt]{article} \usepackage{graphicx} \addtolength{\textwidth}{1.5in} \addtolength{\hoffset}{-1.in} \addtolength{\textheight}{2.0in} %\addtolength{\voffset}{-1.68in} \addtolength{\voffset}{-0.8in} \newcommand {\rreal}{\mbox{$R\!\!\!\!\!l\,\,\,\,$}}...

Hi Apparently a long TE gives a good T2 image yet how is TE length selected? If I stand in a cave and shout I don’t control the time that the echo gets back to me, right? Cheers Ian

Homework Statement A 10-km-long underground cable extends east to west and consists of two parallel wires, each of which has resistance 13 ohm /km. An electrical short develops at distance x from the west end when a conducting path of resistance R connects the wires (Fig. 27-31). The resistance...

If I have a resistor and a voltage source in series but then I apply a short circuit in parallel to both of them would the voltage source and resistor not receive 0 V? Thus having 0 current. What would change in the circuit?

Homework Statement A short metal cylinder 145 mm in diameter and 145 mm high at 1045 K is suddenly exposed (all sides exposed) to a room air temperature at 300 K with h=25 W/m².K. Assume that for the metal k=40W/m.K, den=7800 kg/m3 and Cp=c=600 J/kg.K. Estimate (a) the time required for the...

IO9 article on the ESP Into the Black Writing contest: http://io9.gizmodo.com/write-a-short-story-about-the-economics-of-the-future-a-1800020162 Due date in November 1st 2017 with a prize of $12000 for 5000 word or less short story about economic security in the future. Jedi

Homework Statement How to short the opamp 's inputs together. Below is schematic of circuit. Homework EquationsThe Attempt at a Solution This is first time that I heard " Short Inputs " .It 's terrible to me .I don't know how to short it . Could you help me about this, ?. Please you illustrate...

The shorter leg of an integer-sided right triangle has length 2001. How short can the other leg be?

Hi, I am currently writing a short story where a character travels to the future. This universe operates much like the George Ellis hypothesis where the future is not defined yet and we are always in the leading edge known as "now". Therefore, by traveling to the future he/she comes to a place...

I work at a electric arc furnace. We measure a lot of items on our furnace and found that some weeks we preform well and other we do not (kwh/ton). With everything else being equal i believe that the utility's available short circuit current is affecting this. The utility feeds our substation...

Homework Statement HI! I'm in need of some help to come with an interesting physics-related topic for a short, five-minute presentation. We'll be graded by our ability to speak well rather than our physics knowledge, so I want to talk about something simple, straight-to-the-point and not too...

I see a lot of posts here in the writing and world-building forum that ask for help in creating a story, but I rarely see any actual stories! Perhaps you've never shown your writing to anyone else or maybe you've never gotten to the part of writing where you actually do some writing (it's quite...

I would like to know if is safe to stay in Sendai (less than 100 km from Fukushima). I have read different information in internet but I think is better to ask a expert, I am not sure about the radiation since it seems is not stable, it could be between 0.4-0.6 msv if I understood, is that ok to...

In the circuit in the image attached, why does no current flow between C and D? I've been told it's a short circuit I just don't see why, there is a resistor in that branch. The source is connected between terminals A and B.

Hi, Silly little question about the transformer short circuit test. When I perform it with the secondary shorted and I get Req = Power / current2 is this Req = Rpri + Rsec? If I measured Rpri and Rsec with a multimeter? Thanks

When we try to measure shorter and shorter distances. eventually we have to put in so much energy into such a small space that it creates a black holes, thus makes it impossible see inside. So there is a limitation to how small distances we can measure. Exacly how does this happen? Why do we...

Homework Statement "Prove: ##∀n∈ℕ##, ##3^n>n^2## Homework EquationsThe Attempt at a Solution (1) We will prove that ##3^n>n^2## at ##n=1## ##3=3^1>1=1^2## (2) Now assume that ##3^k>k^2## for some ##k>1## (3) We will prove that ##3^{k+1}>(k+1)^2## or ##3⋅3^k>k^2+2k+1## Note that...

From practice (pls don't call police), I know that it is much easier to knock down short people. A tall person of equal mass is more difficult to knock down on the floor. Theoretically, the taller person should be easier because there's this whole center of gravity thing. But in practice, one...

Homework Statement Recently did a lab experiment were 3 different flight conditions were applied to the same aircraft to see how it affected the aircraft dynamics, we analysed the results by two different methods 1.) calculate using the flight coniditons with a formula sheet and 2.) we printed...

Hi. Some laptop or mobile phone chargers still work for a couple of seconds after being unplugged. I've also seen similar behaviour with the standby lights of monitors, TVs and other devices after they are disconnected from power. Is this due to self-inductance in the transformer? If so: If...

Here are a couple of short stories of mine that you guys are especially going to hate, as they have deliberatly nonsense science in them, IN SPACE!Space 1.. I was bored today so i decided to build a spaceship with an FTL-wormhole-warp-engine-thingy out of some old washing machine parts, a brick...

I think the short story is great for Science Fiction. I grew up reading If, Amazing, analog et.c. And have been reading a lot of SF Short Story Collections lately. In my opinion Asimov was a great short story teller. It seems much easier to have a great idea and tell it that way rather than...

I just learned that "action potential is a short-lasting event" (wiki) If someone is experiencing an emotion of sadness, is that same action potential keeps firing many times back to back or can it actually be a possibility that an action potential lasts for a "very long time". I am guessing...

Does this paper [https://arxiv.org/pdf/1505.06963.pdf] give sufficient reason to accept/believe that the infinities where we "find" singularities can never really happen because there is a minimum length scale that prevents it? Hoping that I have made at least a reasonable deduction from the...

A stock, in the first year, cost 128 dollars; in the second, cost 64... D - Price 1 - 128 2 - 64 3 - 32 4 - 16 If I buy 100,000 dollars of this stock @ 128 dollars / share, so, in the second year I will lost 50,000 dollars (50% of 100K). In the third... ok, ok, easy... When I buy stock, my...

I am looking at a statement that, for a short exact sequence of Abelian groups ##0 \to A\mathop \to \limits^f B\mathop \to \limits^g C \to 0## if ##C## is a free abelian group then this short exact sequence is split I cannot figured out why, can anybody help?

Homework Statement In the figure in the picture uploaded assume that the switch has been closed for a long time such that the inductor acts like a short circuit. Through which resistors does the current pass through and why?? Homework Equations A short circuit is basically a wire or a zero...

Homework Statement Flat harmonic electromagnetic wave propagates in the positive direction in vacuo axis y. Vector electromagnetic energy flux density is given by: S(y,t)=Sm *cos(wt-ky)2.Wave value: k=(2*π)/λ=0.41 m-1,Amplitude Sm=26 W/m2.Compare this wave with another wave. Homework Equations...

I have one pretty basic question... What are the types short, long etc used when creating for example integers used for? Whenever I read the description, it says "it's able to store bigger numbers", but to be honest I don't see any practical use of/visualize such a description... Why would I...

I am sure these are wrong given what is 'proven,' I just can't put my finger on it. Any insight into what is wrong is most appreciated. Thank you in advance!:1) Let q_1, q_2, q_3, … be an enumeration of A = \mathbb{Q} \cap (0,1).2) Select a real number r \in (0,1)...

Hello! I have this problem f'(x)=f(2-x) and I need to find f. This is what I did x -> 2-x f'(2-x)=f(2-2+x)=f(x) => f''(x)=f'(2-x)=f(x) => f''(x)=f(x) => ##f(x)=c_1e^x+c_2e^{-1}##. So, ##c_1e^x-c_2e^{-x}=c_1e^{2-x}+c_2e^{x-2}## => ##-c_2e^{-x}=c_1e^2e^{-x}## => ##-c_2=c_1e^2##. And, similarly...

Homework Statement Homework Equations p=nsf δ=mϒ Kd=[sin(δ/2)]/msin(γ/2) Kp=cosε/2 e.m.f=4.44TφfKdKp The Attempt at a Solution i do not know why pole pair =2 and it is short 2 pitch. how can i find pole pair and short pitch from its original developed diagram? i know that Phase spread=60(we...

Hi guys, my friend’s birthday is coming up and, as a gift, I want to make him a comic with a clever and/or funny punch line. It’d be nice if it were somewhat related to his interests and hobbies which include gaming, 3-D printing, and he also messes with his raspberry pi a lot. Now, the problem...

Homework Statement Homework Equations V=IR Current Loop method, KCL, Node Voltage The Attempt at a Solution I am struggling with this problem because I haven't seen a circuit like this before. I think I found the Voc correctly (4V) but I am stuck with finding the short circuit current. I...

So far, I have only seen about 3 LIPUS (Low Intensity Pulsed Ultrasound) devices that are commercially available. The one that I am looking at right now is made by Bioventus Global and it is called Exogen.The " http://www.exogen.com/us/patient-resources ", on Bioventus Global website, states...

So I am completely new to coding. I told my advisor that I wanted to work with him despite my lack of experience so I can get some experience. He said yes, and in fact he is a very nice and helpful advisor. He does think I need to work faster, and I felt that way too but I don't know how to. I...

Is there a short path to becoming a nuclear engineer if you have a B.S in physics? Can you get into grad school and specialize in nuclear engineering?

Hi, I'm trying to wire a transformer which steps my mains voltage (240VAC) down. I just finished wiring the the primary to the plug, and thought I should test my connections by plugging it in. The coil was not inside the core or near the secondary, it was just lying on a piece of paper. I...

Hey! :o Let $R$ be a commutative ring with unit. We have that if the sequences $0\rightarrow A\rightarrow B\overset{f}{\rightarrow}C\rightarrow 0$ and $0\rightarrow C\overset{g}{\rightarrow}D\rightarrow E\rightarrow 0$ are exact, then the sequence $0\rightarrow B\overset{gf}{\rightarrow}...

Homework Statement Determine the vector potential due to a short wire running from (−L/2, 0, 0) to (L/2, 0, 0) carrying a current I = I0cos(ωt) (consider only points at distance r >> L from the origin). (You may neglect the effect of the return circuit.) Now determine the corresponding scalar...

For this question I'm focusing on part B 1. Homework Statement Three similar coils, connected in star, take a total power of 1.5 kW, at a power factor of 0.2, from a three-phase, 415 V, 60 Hz supply. Calculate: a) the resistance and inductance of each coil; b) the line currents if one of...

I recently read somewhere that this is considered one of the very best science fiction stories of all time, so I got a copy and read it. I have to say that I don’t see what all the fuss is about. POSSIBLE SPOILERS - First, Asimov created an alien world populated by beings that for all intents...

Hello all. I am not a physicist and would probably be considered a "physics idiot" by people on this site, so please excuse any ignorance on my part. I am writing a book and need some help with the physics of nuclear weapons. For the purposes of my book, I am looking to have one of my...

(sorry, I couldn't figure out how to insert an image from my drive) I have a problem where in finding the thevenin resistance I take out my independent sources and as a result I'm left with a resistor parallel to a short circuit. Should I ignore this resistor when calculating equivalent...

I've searched around and all I can find are people quoting the equations. I see it in the math, but it seems contradictory. Here is my line of thought: 1. A source maintains a voltage difference across its terminals. 2. The difference in voltage causes charge to flow from higher to lower...