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3

Yes you can :) How did it work out for you?


0

Clearly, the water may be in direct contact with the 220 or 230V phase line voltage inside the shower head. But normal tap water has a high resistance, and this resistor (of the water touching the body) is in series with a user's body resistance. It is not (directly) the voltage that is dangerous, but the resulting current that may flow through the human ...


2

If I read the description correctly, your experiment is set up to impart an initial velocity to the coin before your timing starts - as you drop it from slightly above the edge of the table, but don't start timing until you hit the edge (hear the impact). At the moment of impact, the center of mass of the coin will slow down a little bit - but it will still ...


3

I just add to above points which are mostly correct my two pennies. 1- the wire is loaded with a history of residue strains from the manufacturing and handling so the stiffness and elasticity of it is not homogenous lengthwise or even along cross-section. if you'd write the whiplash DE's in a finite element software it is not a linear differential equation ...


72

Your wire is not quite round (almost no wire is), and consequently it has a different vibration frequency along its principal axes1. You are exciting a mixture of the two modes of oscillation by displacing the wire along an axis that is not aligned with either of the principal axes. The subsequent motion, when analyzed along the axis of initial excitation, ...


12

UPDATE : After looking again at the video, I agree that Floris' explanation seems to be correct and my explanation below is wrong. Slightly different frequencies of vibration in two perpendicular planes accounts more simply for a rotation which reverses one way then the other. Kinetic energy seems to decay constantly; it does not seem to be stored in an ...


4

Get a microscope slide or equivalent thin piece of clear glass. Paint the central portion with india ink or spray with black paint. The coating should be thick enough to prevent the passage of light. Let dry. Using a razor blade and a thin straightedge, scratch a thin line through the paint across the slide (perpendicular to the long direction). As close as ...


41

The angle between maxima in the double-slit pattern is $$ \theta \approx \frac\lambda d $$ for wavelength $\lambda$ and slit separation $d$. I wild-guess that the slits in your photograph are about 5 cm apart, so your diffraction peaks should be separated by $$ \frac\lambda d = \frac{\rm 500\,nm}{\rm50\,mm} = 10^{-5}\rm\,radian $$ which is too small for you ...


1

I cannot find sources confirming this (apart from some google books results, but those were all collections of wikipedia articles). Somewhat related is this source: "Dehydration of Ethanol-Water Mixture Using Activated Carbons from Sawdust and Palm Kernel Shells". The abstract says that the sawdust was chemically activated with ammonium chloride as catalyst, ...


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This is somewhat conjectural, but I think that sawdust is selective in terms of how polar the liquid is. Water and ethanol are both polar, but water significantly more so (ethanol is significantly less nonpolar at the CH3 end). To determine if this is indeed the case, I tried pouring some very low-viscosity (so that it tends to ball up less) cooking oil on ...


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Voltage is 6V. There's a "current sense resistor" of .05 ohms followed by another resistor of say 1K. There's 1A flowing. This is not consistent. If you apply 6 V to a total resistance of 1000.05 ohms, you'll have a current of about 6 mA. If you want to have 1 A flowing, you need to apply about 1000 V, not 6 V. I'll assume you've adjusted the voltage ...


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This type of shower head is used in Central and South America and so other parts of the world and is sometimes called the "suicide shower" by those who visit those countries. What you see is the uninsulated conducting element which make the transfer of heat from the element to the water to be heated efficient. It is thus totally unlike the sort of heating ...



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