Head Definition and 411 Threads

Homework Statement Please refer to the image attached for problem statement and diagram. There's an inductor somewhere, but I have no idea where and I don't know how to accommodate for it. I can also see that there's another energy storage device, the spring on the right. I have no idea...

Homework Statement In this device, an arm 8.84g long rotates about one end in a horizontal plane, and the astronaut is strapped in at the other end. Suppose that he is aligned along the arm with his head at the outermost end. The maximum sustained acceleration to which humans are subjected in...

Draw the vectors head to tail so they make a triangle

Homework Statement You are on the roof of a physics building, which is 46.0 m above the ground. Your physics professor, who is 1.80 m tall, is walking alongside the building at a constant rate of 1.20 m/s. If you wish to drop an egg on your professor's head, how far from the building...

Constructive criticism please: In 1975, Hillary Putnam published a paper entitled “The Meaning of ‘Meaning’”, in which he proposed an interesting “thought experiment” (see Putnam, H; “The Meaning of 'Meaning'” In Philosophical Papers, Vol. 2: Mind, Langauge and Reality. Cambridge University...

Which country has the potential to have the highest GDP per head of population if its economy was run perfectly? Can one country run a perfect economy if its trading partners do not? Is there a country that can get by on its own with internal markets?

I'm about to begin a bachelor of science with a physics major. I've already found some books on electrodynamics and relativity and such, but I can't find the motivation nor resources to intepret some of the more abstract mathematics, especially to do with linear algebra, tensor analysis and...

It's been a looooooong time since I delved into fluid properties. I'm trying to predict flow based on a known static head. I have a water column which will result in 6 psig of static head. The height of the water column will not change during the flow. I know the downstream piping will...

Hi everybody, The area of a tennis racquet head size is like an egg shape, not oval shape. how to calculate it? Thank you so much for your help ^_^

Just asking the PF members out of interest (and because this stupid Dragonforce song won't go away). Which songs always get stuck in your head?

Homework Statement Heated air at 1 atmosphere and 35 deg. Celsius is to be transported in a 150 meter long circular plastic duct (smooth) at a rate of 0.35 cubic meters/sec. If the head loss in the pipe is not to exceed 20 meters, determine the minimum diameter of the duct. Homework...

"A fair coin is flipped repeatedly. What is the probability that the 5th tail occurs before the tenth head?" What I have so far: So the 5th tail has to come before 10th head. So if we take getting a tails as success and after the 9th head, we MUST have 5 tails --> we can only have 14...

Homework Statement A bug lands on top of the frictionless, spherical head of a bald man. It begins to slide down his head. Show that the bug leaves the head when it has dropped a vertical distance 1/3 the radius of the head. Homework Equations Not sure. Maybe: E_f - E_i = 0...

So, I've been very busy shopping around for labs to apply to for my Phd thesis. Last week I went to a conference where I heard a talk on a new discovery that really captured me and made me want to to my thesis work there. I looked the guy up and it turns out, he's from one of the top tier...

Coin toss with rule "+1 if it is a head and -1 otherwise" 25 < my age < 54. Start from the number of my age and toss a fair coin, plus one if it is a head and minus one otherwise, on average, you need to toss 210 times to hit the bound, i.e. 25 or 54. There are two integers satisfying the...

because I keep getting jammed up here, Using u substitution \int \frac{dx}{e^x} I don't see what else to let u equal besides e^x. ...

Hi all, I'm sure a lot of you know about the head loss due to sudden expansion: Hl = (1/2g)*(v1-v2)^2 This equation can be derived from Bernoulli, continuity and momentum balans equations. The underlying assumption in deriving this equation is that the pressure just after the expansion...

Mmmmmm, tastes like chicken.

Hi, Does anyone know where does the velocity head (the v2/2g term in the Bernoulli eqn.) fits in when designing a piping system? i.e, what useful practical information can one have by calculating the velocity head? Thks

Hey guys, what is that ringing sound we hear in our head? I read in a taoist book that if we concentrate on it, it can finally be silenced and we will hear true silence where every sound will be clear but it won't bother through its clarity in the sense of annoyance but it will be beautiful. I...

I ve got this simple problem and I can can not find the solution. Two men play head and tails. Each man flips the coin n times, every time he has head, he should add one point to his score. At the end, they compare the scores, whose score has more points , the man is the winner. A is the...

I was given an assignment involving finding the head to tail bunch differential acceleration of a beam of muons loading onto an RF cavity, and it occurred to me that my understanding of the concept might be keeping me from working the problem. Can somone concisely explain it to me?

Homework Statement Calculate the head to tail bunch differential acceleration from beam loading on an RF cavity. Homework Equations Frequency 201 MHz Stored energy varies as E^2 Acceleration varies as E Use any other variables that might be needed The Attempt at a Solution...

A horizontal disk of diameter 12.0cm is spinning freely about a vertical axis through its centre at an angular speed of 72 revolutions per minute. A piece of putty of mass 5.0g drops on to and sticks to the disk a distance of 4.0cm from the centre. The angular speed reduces to 60 revolutions per...

Hey, If you have 3 pipes of different diameter flowing into another.. what needs to be true for the head loss in the 3 pipes to all be equal? ie Hf1 = Hf2 = Hf3 Cheers. :S

Homework Statement A neutron collides elastically with a helium nucleus (at rest initially) whose mass is four times that of the neutron. The helium nucleus is observed to rebound at an angle Theta2 = 45° from the neutron's initial direction. The neutron's initial speed is 6.6x 10^5 m/s...

Homework Statement When an electric train runs,we are familiar to the sparks at the end of cable connections.Why does it occur?Is it due to voltage fluctuations? Homework Equations The Attempt at a Solution

This guy sets the world record for kicking oneself in the head. I don't think I will enter this one.:smile:

Here's the free-body diagram of a stupid physics problem I had: http://img211.imageshack.us/img211/5081/triangleey9.png When going over this problem both my book and my lecturer say that \alpha = \theta (they actually don't even mention \alpha; they just write it as \theta to begin with. I...

I installed a shower head in a customer's bath tub last week. The customer was not happy with the flow of water coming from the shower--so I removed the shower head and noted the orfice that leads to the spray area in the shower head was only 3/32" in diameter. I drilled a hole enlarging the...

Hello, I am finished with Calc III and now am in a Mathmatical Methods course. For the first day we were given a "Prerequisites Inventory", basically problems we should know. But I can't do most of them! If you can help me with any I would appreciate it.Homework Statement #4 If cos(24)...

I have always seen these books in the stores, and such, and they're 100 on amazon (which is a heck of a lot better than B&N) and i want them, but then again they'll probably shoot right over my head. I'm working through my first year of high-school physics. I have read quite a few books on...

I know I've been asking a lot of questions lately, but here's another. Does anyone know of a way to unclog the jets on the print head of an inkjet printer? I have the kind of printer where the print head and ink tanks are seperate. I've tried disassembling and soaking them in water, warm water...

1 Dec is \frac {dy} {dx} birthday so we spend the night before at a B&B on the Oregon coast. This was view from our window: http://home.comcast.net/~integral50/hecetaHead/HPIM0326a.JPG here is a bad pic of the B&B. It is in the Heceta Head lighthouse Keepers house...

Two submarines are underwater and approaching each other head-on. Sub A has a speed of 12 m/s and sub B has a speed of 17 m/s. Sub A sends out a 1520 Hz sonar wave that travels at a speed of 1522 m/s. ... I already solved for this question ... ... What is the frequency of the sound detected by...

I noticed that my eye brow hair is substantially smoother,softer and healthier overall than my head hair? I know that part of the answer is that we touch and mess with head hair more but there must be another reason - at the molecular level. And is it possible to make my head hair as healthy?

There's a probability question I saw on the web that looks innocent enough, unless you pay attention to the wording: I have two dice. If i roll them until i get a double, which is the most likely roll to get a double on? The answer given is below: The first roll is the most likely. Heres...

Medical Explanation for Major Depression An important line of defense in treating Major Depression is realizing depression is a medical disorder. It’s a BRAIN disorder, not a MIND disorder (although depression effects the mind). A depressed brain is not running on all cylinders. Certain...

what does everyone think of this? although I've never had anything published nor even submitted anything i think i more or less agree with andrew odlyzko: http://www.cbc.ca/technology/story/2006/10/02/tech-peer.html i think journals like those would enable crackpots to get their...

Hello, I'm not particularly looking for the answers in this problem as much as I am looking for the method to the solution. It's been giving me a headache. 1. Traumatic brain injury such as concussion results when the head undergoes a very large acceleration. Generally, an acceleration...

This is something that arose out of a section in Richard Mould's Basic Relativity. He begins SR with his so-called "Physical Threorms (PT)," which are gedanken experiments used to show the effects time-dilation, length-contraction, and the concept of simultaneity in relativity, in that order...

I saw this on a website. Prove that if r and s are positive integers with r > s and gcd(r,s)=1, then gcd(rs , r + s)= 1. I can think of two ways to show this. Using the Euclidean algorithm or by showing that 1 can be a linear combination of rs and r + s. Funny thing...I couldn't do either...

I have a head unit (HU) for my car (Panasonic) with the ability to connect an external CD changer. The HU connection has an 8 pin DIN and a left and right RCA input for the external CD changer. I was hoping I could easily connect the left and right RCAs to my ipod and connect the 12v and...

Question: An airplane, whose air speed is 600km/h is supposed to flyy in a straight path 35 degrees north of east. But a steady 100 km/h wind is blowing from the north. In what direction should the plane head? Here is an answer by someone(is it right?) Vp (vector velocity of the...

why when you cross the 2 hairs http://img148.imageshack.us/img148/8223/image15dz.png the moment you try to break them up, you would see like they are "somehow connected", is that "static electric" ?

do-it-yourself encryption Really don't know where to put this, so thought I'd ask all the fine folks here and see if I get a response. One of the curses of being widely read is that sometimes you remember the subject but neither content nor location of something you read once and would really...

I was reading on this page... http://www.cda.org.uk/megab2/build/pub125/sec4.htm#5.1 ...and I tried calculating head loss using both the forumla given, and the nomogram. Aren't these supposed to give the same result? Or am I missing something fundemental? Because they don't equal each...

http://www.negative-shock.net/view-409" That woman must be absolutely boneless. :bugeye:

Hi everyone, I've got a problem with solving this one. Two spheres X and Y (no mentioning about them being identical in mass but drawn in equal sizes) are about to collide head on. Their initial velocities are +5ms^-1 and -5ms^-1 initially, moving towards each other with X being towards...

hey guys , i am studying about the old combustion chambers. i came across the L head combustion chamber and am confused about the exact position of the spark plug.so please help me out of this.