What is Amplification: Definition and 84 Discussions

Polar amplification is the phenomenon that any change in the net radiation balance (for example greenhouse intensification) tends to produce a larger change in temperature near the poles than the planetary average. This is commonly referred to as the ratio of polar warming to tropical warming. On a planet with an atmosphere that can restrict emission of longwave radiation to space (a greenhouse effect), surface temperatures will be warmer than a simple planetary equilibrium temperature calculation would predict. Where the atmosphere or an extensive ocean is able to transport heat polewards, the poles will be warmer and equatorial regions cooler than their local net radiation balances would predict. The poles will experience the most cooling when the global-mean temperature is lower relative to a reference climate; alternatively, the poles will experience the greatest warming when the global-mean temperature is higher.
In the extreme, the planet Venus is thought to have experienced a very large increase in greenhouse effect over its lifetime, so much so that its poles have warmed sufficiently to render its surface temperature effectively isothermal (no difference between poles and equator). On Earth, water vapor and trace gasses provide a lesser greenhouse effect, and the atmosphere and extensive oceans provide efficient poleward heat transport. Both palaeoclimate changes and recent global warming changes have exhibited strong polar amplification, as described below.
Arctic amplification is polar amplification of the Earth's North Pole only; Antarctic amplification is that of the South Pole.

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  1. E

    NPN transistor overheating even when used with appropriate parameters

    I have been trying to build a simple Current control circuit using a NPN TIP35C transistor but have run into the problem of it constantly over heating and being destroyed. The transistor is the only component that heats up whilst it is on. The supply voltage is 10V, well below the Max and at the...
  2. PhysicsTest

    Engineering Is My Understanding of the Current Amplification Circuit Correct?

    I have taken portions of a schematic for amplifying the current I1, this I1 current is the phase current from one of the legs of the inverter. The output vout1 is the amplified voltage, again given to a micro which has internal opamp. Is my circuit understanding correct? When I give I1 = 10...
  3. G

    B How to calculate the amplification of a cone

    Some where I read as sound travel away from the source its volume become 50% less every time cross sectional area doubles. Like throwing a rock into the lake wave rings get larger and larger diameter as the wave travel away from the rock. It seems to me same thing should happen in reverse...
  4. Charlie Cheap

    Tube amplification vs solid state

    I am certain this has been answered...but I missed it. Why do so many guitar players swear by TUBE amps? My son-in-law says they just sound better. Because I was a TV/Radio service tech for 20 years with a degree from Elkins Institute, he asks me why? My guess was, maybe amplifying a signal...
  5. H

    I Proof using Rule of Disjunctive Amplification

    Book shows a proof where a conclusion is reached of: ##\neg r##. The next step says ##\neg r \lor \neg s## using the rule of disjunctive amplification. The rule of disjunctive amplification as I know it is ##p \implies p \lor q##. I don't see how from this you can also say ##\neg p \implies...
  6. runningman19

    Design of an Op Amp Circuit for Voltage Amplification

    Hi Everyone, I would like to measure voltage output from a sensor via an Arduino. The sensor outputs 20 mV at max capacity. I'd like to bump this up to around 5 volts so it is easier to measure. My plan was to use a non-inverting topology coupled with an LM393N op-amp. The schematic for a...
  7. V

    Amplification Cycles and Cycles of PCR

    Homework Statement A sample undergoes 35 amplification cycles. How many copies of the target sequence has been produced after 30 cycles of PCR? Homework EquationsThe Attempt at a Solution 2n=230=1073741824 Is this correct? Im just a little confused as to what the difference is between...
  8. D

    Why does piezoelectric need amplifying?

    Homework Statement Descibe[/B] in detail the contruction of a piezoelectric device (ultrasound machiene) and how it works. And explain why the singal from that device need amplification Homework EquationsThe Attempt at a Solution Electrical current passes to the piezoelectric crystal...
  9. D

    A Helmholtz Resonator: attenuation vs. amplification

    Hello guys, I read the other threads about HR, resonances and so on, but I couldn't find a clear explanation of what the practical implications of using a HR are. From one side, HR is described as a "reactive element", used in several contexts to attenuate a specific noise by means of...
  10. OldWorldBlues

    Trouble understanding common-emitter amplifiers

    Hi there! I've been tinkering with some homemade speakers, and wanted to make a simple amplifier circuit to step up the some 3 volts that comes out of an aux jack to 9 or 10 volts. I decided that the common-emitter model looked the easiest to understand. I was mistaken. This is the simplest...
  11. G

    Boosting AC Signal for Solenoid: Techniques for Current Amplification

    Hi, everyone. I'm working on a project right now where I need to amplify an AC signal to create as much current as possible in a solenoid to generate as strong a magnetic field as I can. I'm likely dealing with a maximum of 10 V and 10 mA from my signal generator, but I ideally need a peak...
  12. Erik Ayer

    I Light amplification with open-ended laser tube

    Is it possible to get a laser tube with the ends unmirrored, designed such that a photon being sent through will have a good chance of stimulating another photon to be emitted? If this is possible, then a beam of light going into the tube would be roughly doubled in intensity. When stimulated...
  13. Pushoam

    Voltage amplification done by a transistor amplifier

    Homework Statement Homework EquationsThe Attempt at a Solution The equivalent circuit is drawn below. It is assumed that the potential drop across the pn junction in forward bias is 0 V(I can't take it 0.7 V as the input voltage is 0.5 V). In this case the p-n junction is equivalent to a...
  14. Vaughan

    Post sound amplification electronic crossover/devider

    Hi Guys, Im new here and don't know much about electronics so please bare with me as I try to explain what I would like to know. If you have a classic design speaker it has a passive crossover inside consisting of mainly capacitors and inductors changing the frequency (or limiting) to send low...
  15. Dante Meira

    Does the weight of a lever influences the amplification?

    According to Wikipedia: Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. Ideally, the device preserves the input power and simply trades off forces against movement to obtain a desired amplification in the output force...
  16. K

    Calculating the amplification of a transistor

    Homework Statement In the circuit shown below, I have to find the amplification for when the commutator which connects to the 4 kΩ resistance is open, respectively closed. We know the Beta factor to be 200, and the current through the base is negligible. The transistor is made of silicone...
  17. T

    Transfer functions of active filters with Amplification

    Homework Statement Derive the transfer function for both circuits \frac{V_{out}}{V_{in}} sketch Bode plots for each circuit (amplitude and phase) Homework Equations Z_c=\frac{1}{j{\omega}C}~and~{\omega}_C=\frac{1}{RC} The Attempt at a Solution We can treat this as a potential divider using the...
  18. mfb

    Amplification of RNA by an RNA polymerase ribozyme

    I stumbled upon this publication (News at phys.org). As far as I understand, it is a big step towards replicating RNA systems. They found an RNA enzyme that can synthesize longer RNA molecules, and fully replicate shorter RNA molecules - completely without proteins. It cannot replicate itself...
  19. Nelson Luis

    Amplify Arduino PWM with LM324 to 0-10V

    I am using the LM324 to amplify the signal arduino pwm from 0-5 volts to 0-10 volts, but with the source of 5 volts can not amplify :( ... someone can help me to amplify this signal pwm
  20. directbydirecct

    A Deriving Amplification of Images in Schwartzschild Metric

    In the paper Strong field limit of black hole gravitational lensing, the amplification of images in the Schwartzschild metric was given by $$ \frac{1}{\beta}\sqrt{\frac{2\,D_{LS}}{D_{OL}D_{OS}}} $$However the authors did not derive this expression or explain its origin. Does anyone know how to...
  21. Sveral

    Choosing the Right Voltage Gain for Frequency Amplification | 250 Hz to 50 kHz

    How do I know, how big of a voltage gain for an amplifier do I need, if I want to increase the input frequency from 250 Hz to 50 kHz? Thank you.
  22. Dan15

    I How does negative power link to amplification?

    So I've been studying electrons behavior in a semiconductor superlattice and I am currently analyzing the negative slope for the drift velocity against electric field. This is where negative differential velocity (NDV) takes place. I understand how NDV leads to negative power, but I can't quite...
  23. C

    Binoculars and light amplification

    http://www.rocketmime.com/astronomy/Telescope/Magnification.html im studying from above how image is magnified in a binocular or telescope. In binocular say 7X. can you say light is amplified or jus magnified? if amplified, is it 7 times? if just magnified and not amplified. how come using...
  24. TheOfficialAB

    LASERs: Why is population inversion required for amplification?

    Hi, I'm doing a module on quantum optics and lasers. Most of the texts and online source I have read simply state that 'population inversion is essential for amplification in laser operation'. My question is, why? Amplification/Gain is essentially the result of stimulated emission. Can't...
  25. T

    Amplification of sound in a pipe

    How loud would a 105 db speaker be in a 3 inch metal pipe?
  26. synMehdi

    How Can You Effectively Amplify a 868 MHz Signal for Phase Detection?

    I have an Antenna that receives signal coming from a wide band of distances, 10-2000 meters from a 10mW transmitter. I am working with 868 MHz band. What is the cheapest method ( or cheapest circuit ) to amplify this signal with an Automatic Gain Control LNA so that the received signal stays...
  27. Machinekraft

    Torque Amplification: Is It Over Unity?

    In torque amplification, torque is multiplied without change in its input speed. Then this amplifier if coupled inbetween a motor and gene rator would it not be a over unity machine?
  28. Z

    Wave Amplification & Frequency Transformation

    I understand the concepts behind the terms in the title; however, I have a question about how to transform the wave energy itself. I'm working on a science fair project that involves transforming sound energy into electrical energy--I understand this is not a very reasonable method of harvesting...
  29. T

    Is there a difference between Emergence & QM Amplification?

    I recently read the published article: Stuart Hameroff, How quantum brain biology can rescue conscious free will. Front Integr Neurosci. 2012; 6: 93. PMCID: PMC3470100 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3470100/ From this it seems that current neuroscience views consciousness as an...
  30. H

    Photodiode Amplification

    I am using (attempting to at least) a photodiode to count fringes from a Michelson interferometer. Here is the amplification circuit I am using: Coming out of the op-amp into the comparator I get about 4.2V in a well lit room, 2.17V in total darkness, and 2.33V when the brightest part of the...
  31. S

    RF amplification to power IR LED

    Hello, I am new here so my apologies if I have posted in the wrong place. I am trying to amplify the radio waved I get from a receiver to power led that will ultimately be used as a remote for the AC. I have contemplated "charging" a capacitor until it has enough power to power the led...
  32. H

    Current Amplification w/ ICL8038 & LM741: Can I Get 1A?

    Homework Statement I had a circuit in lab using an ICL8038 function generator IC, and was using the sine wave output from the chip. I am being asked to add components to increase available current to 1A. The chip pulls a steady 13mA, but I derped and didn't check output current. The spec sheet...
  33. T

    What Is the Current Amplification Ratio in a Bipolar Junction Transistor?

    Homework Statement If IB and IC (IB = Base current and IC = Collector current) of bipolar junction transistor are 1mA and 100 mA respectively, determine its current amplification ratio in common emitter configuration.Homework Equations IC=β*IB Where β = current gain = \alpha/(\alpha-1) (is this...
  34. S

    Transistor amplification related doubts

    I understand the basic concept. A small change in the base current will lead to large change in the collector current and will lead to amplification. But the question is, the small change in base current is brought by input signal or the biasing? Also the coupling capacitors allow only the ac...
  35. A

    Sine wave power amplification question

    Hello all, I'm new to electrical engineering, and I'm working on a project that requires a bit more than I'm familiar with. What I'm asking for help on boils down to this: I have a circuit that outputs a low power sine wave (frequency 25-40kHz) with an amplitude +/- 5V at a few watts. I want to...
  36. B

    Large-Scale Wave Amplification - Is it plausible?

    I'm currently writing a novel regarding a civil war on an alien planet - I plan to keep the book fairly grounded in realism with the exception of the existence of the aliens themselves. (This also means that there's no FTL-travel; the story remains on one planet, and humans do not make an...
  37. E

    Raman Amplification: Understanding its Role in Optical Fibers

    Hello I understood what is the meaning of Raman scattering whether spontaneous or stimulated but I did not understand its importance in the optical fiber The amplification role is to compensate the loss on the fiber of the signal but how did we do it in the fiber !? Thank you
  38. N

    Finding current and voltage amplification via load line graph plotting

    Homework Statement This is a question refer to a transistor in a common emitter configuration. And this is the table with data of Vce and Ic at certain range of Ib stored in microsoft excel, and the graph is plotted within the file attached(in another tab)...
  39. S

    Sound amplification decreases when connecting a capacitor

    Hi, An electronics newbie here.. I'm trying to produce sound using a 555 timer. When I tried using the schematic(attached file), a definite sound came. But when I removed the capacitor C2 in the circuit, the sound (amplitude) actually increased! Why does this happen? Why then, do we use a...
  40. S

    Passive amplification of a specific audio frequency range(microphone)

    Hi, I want to passively amplify a specific audio frequency range of a microphone. When I say passively I mean by non-electronic means - no op-amps or transistors. Like a speaker can be designed for specific frequency range - a woofer/tweeter/etc... I presume this works in the other direction -...
  41. S

    Photon conservation in Raman amplification

    Part 1: Homework Statement Use two coupled-wave equations for the Raman amplification process depicted to the right to show that for every photon at Stokes frequency omega_s created (destroyed) one photon in the laser pump field omega_L is destroyed (created). I have the coupled-wave...
  42. J

    Is Amplification same as gain?

    Hello, I can't figure out what's the difference between the two: Gain - how much the amplitude of the signal was increased/decreased Amplification - how much the amplitude of the signal was increased/decreased If we take a basic inverting amplifier circuit: http://alturl.com/39n78 We...
  43. C

    Current amplification without external sources

    i want to amplify my current from 300mA to 600mA. i m making a solar charger and the specifications say 6v 400mA. however i m unable to receive 400mA.. is there a way to amplify current to 600mA from 300mA.. i can lower my volt to 5V from 6V. i don't want to use any external dc or ac supply
  44. I

    MOSFET Small-Signal Amplification

    Hi everyone, I am trying to learn about circuits from some slides I obtained and I am stuck on a slide. Here is a screenshot of it (it is in German): http://i.imgur.com/HCtWF.png It says: Example: Illustration of maximum achievable amplification of a MOSFET with the use of the...
  45. N

    Ear Ossicles Amplification: Synovial Fluid Present

    How do ear ossicles help in amplification even when there is synovial fluid present?? The ear ossicles help in amplification of received sound (right?). We know that the joint between the three ear ossicles is synovial joint. Therefore, we have synovial fluid to prevent friction. This...
  46. C

    How voltage amplification affects plasma flux density?

    Would a voltage amplification with the same power output increase plasma density and increase the magnetic field of the plasma, if the power output does not change? In the case of a USB plasma globe with a current flow of 300mA through 5 volt, amounts to 1,5W. CASE A: Ofcourse this...
  47. A

    Which H-Bridge driver can I use for power supply amplification?

    I have been tying to design and build a dc to ac inverter. I want to convert 10v dc to 25v ac @ 50hz. I want to use a pic24h microcontroller to generate pwm waveforms to control a H bride driver. I have programmed the pic24h to produce pwm waveforms. I used the LMD18200 as the h bridge driver...
  48. C

    How to get started for building the amplification circuit

    I am planning to build the amplification circuit to amplify the signal from my signal generator by myself. Can someone tell me the what type of materials are necessary for me to get started? What kind of book will be helpful?
  49. T

    Light amplification jet engine?

    Using a series of focal reflectors, built in antenna strategically placed for proper phasing the EMF amplification system. Kinda like a space hyper engine. Possible? I can draw some blueprints I think.
  50. Femme_physics

    Basic electronics problem with an amplification factor for a transistor

    Basic electronics problem with an "amplification factor for a transistor" ((I think it still counts as "introductory physics" -- let me know if I'm wrong!)) Homework Statement http://img600.imageshack.us/img600/7950/back1j.jpg http://img690.imageshack.us/img690/999/back2wzt.jpg...