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This depends quite a bit on what you're willing to accept as "direct." The magnetic force between two parallel current-carrying wires can be interpreted as being due to Lorentz contraction, and that's quite easy to measure -- you can do it with a battery and some strips of aluminum foil. Some measurements can be interpreted as showing time dilation, but in ...


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There are, by my count, 33 other official weather observation stations within Sydney. Here's a map: With regard to the Sydney - Observation Hills (Station ID 066062) station -- That freeway didn't exist when the station was built. How could it? That station dates back to 1858. The station was moved 150 meters to its current location in 1917. That tiny ...


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It no doubt does. Solar radiation will heat surfaces, and the rate at which a black surface absorbs that heat is greater than for other colors. That heat is then partly lost by radiation, partly by conduction, and partly by convection. If you assume the last two terms will be the same regardless of the color, then you can see why a black surface will become ...


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When you run into a problem like this, there are several things to consider: Systematic error. For example, when you say "three, two, one, go" you never release exactly on "go" (plus, there is a time delay between when the person says "go" and when you hear it...). Other example: the floor is not level (as suggested by ACuriousMind). When you measure the ...


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You do exactly the same thing: you "rotate" the state and then measure along whatever axis your measurement apparatus happens to measure. The only difference here is that the "rotation" does not necessarily correspond to a rotation in space like it does for a true spin. What follows is a detailed description of how we do rotations of a generic 2 level ...


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If you look at this video which claims to be a "world record spin", they claim they measured the speed (308 rpm!) with a "Sport Tach" - see for example review at http://figureskating.about.com/od/accessories/gr/sporttach.htm . Tried to follow links to their website - it seems their domain is for sale so I suspect they have gone out of business. When you ...


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If you don't want to do video, you could try with a smartphone. There are apps which can record the sensor measurements, including the accelerometer and the gyroscope. I have no idea how noisy the data will be for a skater, but if the device is firmly attached to her body close to her center of mass, it may deliver useful results. From there the sky is the ...


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In this link you can find a video analyzer tool. This tool works well with videos taken even on a smartphone, and is free and made for educational purposes. https://www.cabrillo.edu/~dbrown/tracker/ Have her hold a distinct red kerchief or ball in one hand. This way the tracker can easily track her spinning. You can get frequency as well as number of ...



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