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57

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 ...


5

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. ...


3

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 ...


2

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 ...


2

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 ...


1

This could be probably the closest one that I know: Data Analysis in High Energy Physics: A Practical Guide to Statistical Methods Olaf Behnke (Editor), Kevin Kroninger (Editor), Gregory Schott (Editor), Thomas Schorner-Sadenius (Editor) ISBN: 978-3-527-41058-3 http://eu.wiley.com/WileyCDA/WileyTitle/productCd-3527410589.html Especially Chapter 11 is ...


1

What I assert is that instead of the line being formed because it 'follows the path of an electron or muon', it is a chain of interactions. That is, there IS a disturbance, but the path begins with an electron-atom (or even an atom-atom, doesn't matter) interaction, and instead follows like a row of billiard balls (atoms) hitting each other and revealing ...


1

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 ...


1

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 ...


1

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 ...


1

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} = ...


1

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 ...


1

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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