Peak Definition and 253 Threads

This is the only question in my physics section of projectiles I am having trouble with (This is ranked as the hardest question in this section of my text, please cut me some slack :P), because I have no idea how I would go about finding the intersection point of the skier with the slope. The...

Hope somebody can help me. I`m currently doing analysis of determining single crystal of Zr2Cu on a surface of bulk metal. Through XRD, i determine the peak and compared it with data from JCPDS card. My problem is I don`t know the correct way to compare the theoritical 2theta peak(from...

Hi everyone! I hope you people can help me out at a problem I am stuck with: Homework Statement Find the peak voltage across the capacitor "C" All variables given and an image of the circuit are: http://img36.imageshack.us/img36/580/photo2fsc.jpg The circuit is connected to...

A baseball is thrown upwards. What is the acceleration at the highest point? i thought the acceleration would be 0 since velocity at the highest point is 0 and the derivative of velocity is acceleration. Since velocity is not changing, shouldn't acceleration be 0? However the answer is...

The size of bouncing lumps of charged particles, DM and photons in the primordial universe is supposed to be around 220,000 lyr (= sound horizon since the acoustic speed is approx 0.6c). If we then calculate the angle A subtended at Earth by a lump of this size W, some 13.8 Glyr away D (back at...

I'm running an experiment where I drop a mass (99.7kg) a distance of 1.8m. The load is suspended from a very rigid structure through a steel cable. I currently have a load cell in series with the cable and mass. I acquire data at 1000Hz and my load cell tells me I have a peak force of about...

Homework Statement Find the peak electric field inside a 690 W microwave oven under the simplifying approximation that the microwaves propagate as a plane wave through the oven 's 775 cm^2 cross-sectional area. The Attempt at a Solution ave, intensity (s) = ave power (p)/ 4*pie*r^2...

Homework Statement An LRC series circuit with R = 200!, L = 32mH, and C = 2.5μF is powered by an ac voltage source of peak voltageV0 = 200V and frequency f = 770Hz. Determine the peak current that flows in this circuit. Homework Equations V= IR -L dI/dT +Q/C = 0 w = 2 pi f...

I NEED TO GET A DERIVATION SO THAT I CAN MATHEMATICALLY UNDERSTAND WHY: The peak voltage or current is divided by square root 2 to get the root mean square value.please i need a simple derivation just to understand,i will be very greatful for ur consideration.thankyou.

I have (what may be) a simple statistics question... Say I perform an experiment, and I make a number measurements over a given interval (e.g t=0s to t = 10s, every 1s), and I perform this experiment many times. Now, let's say I make a plot of data vs. time, and I want to find when the data...

Homework Statement I am confused. My thinking was if a voltage source is given in polar form with the magnitude and angle eg. (10 L0o)then it is Vpk and if only magnitude is given then it is Vrms. Is it right. I am really confused. Homework Equations The Attempt at a Solution I...

Hello every1 I hav a basic question bout Design of inverters(Voltage source inverters). Wel Actually what does designing mean? I hav to design a inverter whose output Peak voltage is 50v. The input DC voltage wil b around 55V.I'm using single phase full bridge inverter And i'll b using R...

A coil is located at the center of a long solenoid of radius R = 15cm which has 5x10^7 turns per meter and carries a current I = 16A. The coil is coaxial with the solenoid and consists of 5 turns of wire each in the shape of a square of length a = 5cm on each side.What is the magnetic flux...

http://www.treehugger.com/files/2006/04/peak_copper.php http://www.thenational.ae/article/20080807/FOREIGN/629722880/1013/ART&Profile=1013 Any truth to this, or is this debunkable?

Hi all, I'm very new to this forum and I hope my question isn't too trivial. My problem: I need to analyze some numeric data. I have a sample every second in 17 series. So every second I get 17 samples of data, most of the higher series (10-17) being zero all the time. I now want to...

Maybe you've heard about Hubbert peak aka Peak Oil . Otherwise, this threads should be useful for you: https://www.physicsforums.com/showthread.php?t=172175&highlight=hubbert https://www.physicsforums.com/showthread.php?t=184372&highlight=hubbert The global economy it's entirely oil...

Homework Statement A 5 Micro-F Capacitor, a 65mH Inductor, and a 10 Ohm resistor are connected in series Find the resonant frequency of this circuit. Determine the peak current at resonance, if the peak voltage is 100V Homework Equations Fr = (1/2Pi) Square Root(1/LC) I don't know...

Homework Statement Estimate the peak temperature for a 1 ns versus a 1 ms optical pulse with a total energy of 1 J in a 1 cm^2 spot is incident on a sheet of metal. The metal is 20 thou ( 20 thou = 0.5 m). The metal sheet is mounted on a copper block which is held at room temperature. The...

Homework Statement An LC circuit starts at t=0 with its 2000 microF capacitor at its peak voltage of 14V. At t=35 ms the voltage has dropped to 8.5 V. a) What will be the peak current? b) At what time will the peak current occur? c) What must be the value of the inductor in the circuit?The...

Hey guys. The question I have to answer is What is the color of the peak frequency of solar radiation? Now is there a certain way to figure this out or...very hard to find on the internet... best zach

hi, I am 21 years old 180cm tall and 73kg, I'm an ex smoker. I'm in the process of an army application but need to improve my peak flow. will increasing my vo2 max help and are there any other ways to increase peak flow.

Hi all, I have this stituation. Our favourite football team normally play very well. But recently, when they attended a tournament and they lost all the games ! They even lost to a team that they had never lost before. Their form was very weak at the time. I am not sure if there is a word or...

For the circuit shown a. What is the resonance frequency? b. At resonance, what is the peak current through the circuit? http://img218.imageshack.us/img218/2971/p56dr3.png I solved for resonance frequency knowing that when Xc=XL you get a resonance frequency. my set up was 2pifL=1/(2pifC)...

[SOLVED] Determining Peak Current Homework Statement A light bulb uses 75 watts of power when a lamp is plugged into a wall socket (RMS voltage = 110 volts alternating at a frequency of 60 hertz) Determine the electrical resistance of the light bulb filament. Determine the peak current...

:-p http://www.cbc.ca/consumer/story/2007/09/26/helium-shortage.html

hello i want to find the peak point of a quadratic bezier curve. one approach is finding all distance between "start point","any point on curve","end point" and then choosing then maximum distance between them. but this approach get much time when implementing on computer is there any...

About 200 days ago i made a thread on this forum about peak oil the thread was called hubbert peak. in that post i asked if you realized that peak oil was coming and got by and large a negative response. things like "no peak oil is myth" and "we will find other energy sources" i...

Homework Statement I am assigning m/z peaks on a mass spectrum, and there are 3 peaks not on the chart given by the instructor, and I was wondering if anyone can help me determined their identities. The peaks I am unsure of are found at 95 m/z, 109 m/z, and 123 m/z; I already figured out the...

Homework Statement A circuit contains only 0.197 H inductor. An AC voltage of peak value 166 V and frequency 60.5 Hz is applied to the circuit. When the voltage is 166 V, what is AC current? Answer in units of A. Homework Equations The Attempt at a Solution we know that...

An integral \int\limits_{-\infty}^{\infty} \sqrt{1+x^2} e^{-Ax^2+Bx} dx is the problem. Anyone knowing the solution?

In 1956, Hubbert proposed that fossil fuel production in a given region over time would follow a bell-shaped curve without giving a precise formula; he later used the Hubbert curve, the derivative of the logistic curve, for estimating future production. Hubbert assumed that after fossil fuel...

Homework Statement A 400 loop circular armature coil with a diameter of 5cm rotates at 60rev/s in a uniform magnetic field of strength 1T. a) What is the peak voltage output of the generator? b) What is the RMS voltage output of the generator? The Attempt at a Solution a) My answer...

hi i was wondering if anyone could tell me of any good dc peak detection circuits. the voltages i am measuring are varying by one hundredth of a volt. i have been using the peak detector on the wqikipedia website but the circuit doesn't seem to store the peak voltage as the reading on the dmm...

What is the peak frequency of the Cosmic Microwave Background? Using Wien's Displacement (#1) and then converting the wavelength of frequency (#2), I get 282 GHz. #1. 0.0028977685 / 2.728 = 0.00106223185483871 Meters (1 millimeter) #2. 299792458 / 0.00106223185483871 =...

If a fireworks rocket has an initial upward speed of 58 m/s when launched, for how long will it coast before reaching its peak? So could I use the equation t=v0z/g? When I use this I get the peak to be 5.9s. Is v0z = 58 m/s or would that be 0? Am I approaching this correctly?

Probably they do. However, I've heard there is a difference between guys and girls in that respect.

What are the prerequisites for great new scientific ideas? Intelligence and creativity? Assuming these two variables-feel free to add more if you wish-does the mind ever peak at a certain age in either of these two areas, be it physically or simply subjectively? It seems the true geniuses do...

In the last couple of days I have been searching for information concerning the Hubbert Peak Theory. Most of the information about peak oil seems to be alarmist and/or conspitacy theorist make-preparations-now-or-you're-gonna-die stuff. I have read that most oil companies and the US...

http://www.physorg.com/news8441.html" Sorry folks, but if his right, it means it’s all down hill from here.

Hi, My Question: If the peak value of the magnetic field of an EM wave is 2 x 10^-7 T. Calculate the peak value of the E-field. Work: C=E/B so, 3*10^8 m/s=(E)/(2*10^-7 T) (3*10^8 m/s)(2*10^-7 T)=E E= 60 N/C Is this right ? Thank You

I took a Fathers day hike, thought I'd share the view. Marys Peak is about 20mi west of my home, I haven't been up there in many years, thought it was time for a revisit. these are just some shots along the way. First the requisite waterfalls...

A one bar electric fire has a power rating of 1000W (1kW). If the RMS voltage of the mains is 240V, find the RMS value of the current flowing in the fire and the peak values of current and voltage? Can some one please help me??..Its a past exam question and i don't even know how to start...

The coil of a generator has a radius of 0.14 m. When this coil is unwound, the wire from which it is made has a length of 5.7 m. The magnetic field of the generator is 0.20 T, and the coil rotates at an angular speed of 25 rad/s. What is the peak emf of this generator? Please help me get...

I am always confused with rms value and peak value, so here is the problem: What will be the peak value of the current of a well-insulated 0.03\mu F capacitor connected to a 2.0-kV(rms) 720-Hz line? So first I find the reactance of the capacitor, which is: X_c=\frac{1}{2\pi fC} 7.4k...

There is a projectile that explodes into equal mass fragments at its highest point. One falls vertically with initial speed. I need to find where the other will strike the ground and the energy released during the explosion. I am given the mass(19.6kg), angle (56 degress), initial...

I am really curious as to what the minds on this forum think about Peak Oil. Set to hit around 2010, Peak Oil seems to get an insanely small amount of attention, especially considering that the 1970's oil crash was due to just a 5% decrease in oil production. After Peak Oil, it is...

I have in other threads assumed that the pessimists are correct and that peak oil is happening this decade. Do anyone have more information if this is correct? Can alternatives like tar sands, oil shale or abiogenic oil be dismissed? The peak-oil-this-decade theory is advocated here...

How far from the peak wave do objects emit electromagnetic radiation? Humans emit infrared radiation, but I read that we also emit some microwave also.

how many peak sensitivity of the human eye?

Today is Saturday and it is an unwritten law that on Saturdays one is permitted to post sonnets. Here are the last 6 lines of one by Keats: ... Then felt I like some watcher of the skies When a new planet swims into his ken; Or like stout Cortez when with eagle eyes He stared at the...