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This could be probably the closest one that I know: http://eu.wiley.com/WileyCDA/WileyTitle/productCd-3527410589.html


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The answer is in wikipedia The photograph on the right shows two unusual phenomena: bright spikes projecting from the bottom of the fireball, and the peculiar mottling of the expanding fireball surface. The surface of the fireball, with a temperature over 20,000 kelvin, emits huge amounts of visible light radiation (more than 100 times the intensity ...


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I don't have any special knowledge about this image or nuclear testing, but typically when we see an asymmetry in the evolution of a system, there should be an asymmetry in the laws governing it, or the initial conditions$^†$. There are three asymmetries that I can think of in the system that could explain the asymmetry in the evolution of the system. ...


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Draft and cavitation. Ships cannot afford to have big propeller diameters, they have to make do with the smallest diameter available in order to stay within the draft of the ships' hull. They operate in a medium which is 800 times denser than air, and one important concern is to avoid cavitation. This again means to limit suction peaks and leads to very ...


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If you try to just "cope with the disappointing feeling", you are setting yourself up for the same thing to happen again and again. You need to stand up for your rights, if the situation allows this. But it's unclear from your question, whether this was a case of deliberate plagiarism, or just parallel invention.


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Here's how to measure stellar aberration: Take a telescope and point it straight up. Attach it to something massive and steady, like a chimney stack. Let the scope act like a pendulum. It's fixed at the top, and moves at the bottom. The plane in which it swings is the local meridian. That is, it only swings north-south, not east west. With this setup, you ...


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In classical physics, a system can be described by a set of numbers whose values can all be measured using a single instance of that system. In quantum mechanics, a system is characterised by the values of observables where those values are represented by Hermitian matrices. To describe how information is transferred between quantum systems you have to ...


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Your method is perfectly correct for estimating the error, especially at a high school or early university level. As Farcher correctly points out, it's unlikely for both errors to be at their extreme concurrently, so your error is more like a maximum bound on the error than a typical representative error. The further you go in physics, the more you'll want ...


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Formula for value - $$v_i=\sqrt{{g}\over{2}}RH^{-\frac{1}{2}}$$ General formula for error - $$ \delta v_i = \sqrt{(\frac{\partial v_i}{\partial R}\delta R)^2+(\frac{\partial v_i}{\partial H}\delta H)^2} $$ First Calculate the derivatives - $$ \frac{\partial v_i}{\partial R} = \sqrt{{g}\over{2}}H^{-\frac{1}{2}} $$ $$ \frac{\partial v_i}{\partial H} = ...


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Your method assumes that when one measurement is at one extreme the other is also at an extreme. This is not likely to happen very often and therefore you have overestimated your error. If you have two quantities $A\pm a\%$ and $B\pm b\%$ a better estimate of the percentage error in $A \times B$ or $\frac A B$ is $\sqrt {a^2+b^2}$. The percentage error in ...


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First off, to say that WIMPs are the basis of dark matter is a little misleading. It's a well motivated model that can explain Dark Matter as well as be evidence of supersymmetry, but we have no experimental evidence to support it. It's still just a theory. Another well motivated candidate are Axions which help solve the Strong CP violation. ADMX is an ...


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As someone who did a degree in physics before moving into electronics and s/w R&D, my experience would suggest "yes". Over the years I have been involved in a number of projects that could be classified as experimental physics, and in all cases knowledge of electronics was a vital part. At the very least a physicist should be able to read a circuit ...


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The drag force can be estimated by the following expression: $$F_D=\frac12 \rho v^2C_DA$$ With $F_D$ the drag force, $\rho$ the density of the fluid, $v$ the velocity of the fluid, $A$ the cross-section of the object (perpendicular to flow) and $C_D$ the drag coefficient. This source gives a value of $C_D=1.28$ for a flat plat perpendicular to the airflow ...


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No, this is not possible at least in the way you are implying. Chemical potential as temperature are abstractions that apply to large systems as a whole, because they depend on equilibrium conditions, or in other words, they rely on fluctuations being much smaller than average values. You don't measure temperature directly either, once your thermometer is ...


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The glass carrier has a transmission less than 100% because light is reflected at the air/glass interface then again at the glass/air interface: I'm a bit surprised the transmission is as low as 88% and my recollection is that with normal glass between 5 - 10% of the light is reflected so the transmission should be in the low 90s. However it depends on ...


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Depends, what you want to find out. I would guess that you want to know the transmittance of just your film. Therefore, a reference measurement will be required to separate absorption from your carrier glass from the one of your film. Now, some absorption features could be overlaying. Therefore the carrier glass might obscure some features of the film. To ...


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This link summarizes the measurements of the speed of light. The first measurement of c that didn't make use of the heavens was by Armand Fizeau in 1849. He used a beam of light reflected from a mirror 8 km away. The beam was aimed at the teeth of a rapidly spinning wheel. The speed of the wheel was increased until its motion was such that the light's ...


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In order for a fan or prop blade to deflect air backwards, there has to be air where the fan blade is, obviously. A fan pushes air, and pushing is something that requires physical contact. Wind speed is a measure of the average relative motion of the individual molecules of the air itself: at any given time in an atmosphere there are molecules going every ...


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The magnet may decelerate "at the last minute" if it's sufficiently strong. The difference with the first setup (dropping in a tube) is that the change in flux (and therefore induced currents) in the copper plates is small until the magnet gets very close - the field of a dipole goes with $\frac{1}{r^3}$. By contrast, as you are falling down a tube, there ...


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I just stumbled upon your question. If you go to astrobin.com and put Dobsonian in the search field. You'll see a huge number of excellent images taken with Dobsonian telescopes. Most are of the moon and planets but a few are of the brighter deep sky objects such as the Great Orion Nebula. There are better instruments to use for astrophotgaphy but if you ...



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