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The Rebel

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Everything posted by The Rebel

  1. If its based on the old A-Z then yes these have been available for time. I am always using http://www.streetmap.co.uk to plan my journeys. If you're interested in aerial photos then try http://www.multimap.com I believe the photos were shot using a helicopter that traveled the UK, and compiled a map of britain using the photos.
  2. You want brits to be thought of as eccentric people with emotional issues, suppressed by their wives and with a fetish for giving beats to people from Barcelona????? There are quite a few films that portray us badly but there are just as many if not more that portray us well. For example how cool is James Bond??? and with British films getting more recognition than ever (italian job, trainspotting, bend it like beckham, bride and prejudice, lock stock, snatch, etc.) I don't think a small scene in die hard will do much harm. I should think they see lots of TV over there too, including music artists, etc.
  3. In short, it is the mean angular velocity. I say mean because most orbits are elliptical such that the velocity changes depending on the radius at each point.
  4. http://www.geocities.com/bushatbooker/ ???? Probably debateable, but then all contentious stuff usually is. Take what you will from: http://news.bbc.co.uk/1/hi/uk/1522987.stm - Deployment to middle east 1 week before 9/11 attack http://www.thedebate.org/ - website questioning the ideas of the war on terror (Iraq and Afghanistan) http://news.bbc.co.uk/2/hi/programmes/newsnight/4354269.stm - Secret US plans http://www.alternet.org/waroniraq/21535/ - Secret US plans http://www.gregpalast.com/opeconthemarch.html - Secret US plans http://smh.com.au/articles/2002/10/06/1033538848021.html?oneclick=true - Foreign Policy Agenda http://www.mapsofworld.com/world-top-ten/world-top-ten-oil-reserves-countries-map.html - Top Oil reserves I can't deny I'm suspicious but there is no way of coming up with the answer as there will always be conjecture. As to pro-antiterror campaigns suggest 9/11 and the history of al-queda, saddam, etc. be looked at. Have fun.
  5. Sounds like the microbes that are naturally swiming around your eye, going across your line of sight.
  6. Here's a couple more FYI AAMOF - As A Matter Of Fact AFAIC - As Far As I'm Concerned AFAICT - As Far As I Can Tell ASAP - As Soon As Possible BAK - Back At Keyboard BBL - Be Back Later FAQ - Frequently Asked Questions FYA - For Your Amusement FYI - For Your Information GTG - Got To Go ISP - Internet Service Provider LMAO - Laughing My Arse Off L8R - Later OIC - Oh I See TTFN - Ta Ta For Now TY - Thank You WB - Welcome Back YW - Your Welcome I had a slighter different interpretion of WTF PHI
  7. The Rebel

    Linear Scale.

    Here we are http://mechanical-eng.mme.tcd.ie/~clyons/calibrations.pdf
  8. The Rebel

    Linear Scale.

    Any instrument technician should be able to tell you (or someone that's had some instrumentation training) measuring instruments of this kind are not exactly linear. If you plotted the output of a measuring device against the known input, you'll find that the graph will be sort of exponential but curving off at the top. A bit like a culmulative frequency curve, not sure if there's a formula for it. There is section of this curve however that is more or less linear which is where the instrument is calibrated to by adjusting its "span" and "zero". In essence the scales will only work within their range on the display.
  9. Just a quick tip I've found when I feel a bit close wanting to meet the "porcelain throne", is to suck on an ice cube. And when you think its really close just clench on the ice cube a bit more. I don't know why but whenever I've had too much, this little trick has avoided any embarassing projections. And if you order the right drink you'll never be far from one.
  10. Hmmmm, takes me back to the days of my HNC eletronics . . .. last year. The 1st question has three choices to solve it, Norton's theorum, Thevein's theorum or Superposition theroum. The 2nd seems easier, as its simply ohms law. The power of the generator is given by its emf * circuit current, the dissipation rate is how much the resistance dissipates, and the chemical rate battery emf * circuit current. Efficiency is the power taken by the load (battery) divided by the power supplied by the source (generator)
  11. I can't see this. The flux is emitted in all directions like a light bulb. This flux acts onto a surface area to give luminance. Its, if you like, a measure of how much light is received from a radial source. The intensity is more linear in that it looks at how much "energy" there is at a given distance away. In this case the r refers to the distance from the point source. The formula should actually be I = L / {4 * pi * d^2}. The 4pi indicating where the steradian is. The formulas are used in different concepts, the 1st is as it is received on to a surface, the 2nd is how the source is perceived at a certain distance. Chalk and Cheese clearly even is it is both about light.
  12. It means inverse tan. Another way of writing it would be theta = 2 * arctan(h/2d) also d = h / {2 * tan(theta/2)}
  13. I still think the answer to a) is -40N The acceleration between the two surfaces is 2ms-2. So the answer to a) is 20kg x -2ms-2 = -40N I agree to the workings of b) and c) however. Only my answers would be b) Net force = 720N, Force F = 760N c) a = 7.6ms-2
  14. v^2 is porportional to height, so v is proportional to sqrt of h So a drop that is 1/2 the other, it will finish with a speed of sqrt 1/2 the other. For the second question: Use s=ut + 0.5at^2 for a varying t, remembering that Ted's acceleration will change direction when 0 = u^2 + 2as
  15. Its from the formula Torque = rotational inertia x angular acceleration. Picture the pendulum at a slight angle, the force acting down is mg, so the force along the length is mg cos theta, and consequently the torque force is -mg sin theta. So, [math]T = l * -mg sin \theta[/math] Angular acceleration is simply the second derivative of the angular displacement [math]\frac{d^2\theta}{dt^2}[/math] Rotational Inertia = [math]ml^2[/math] So . . . [math]lmg sin \theta=-ml^2\frac{d^2\theta}{dt^2}[/math] which rearranged becomes [math]\frac{d^2\theta}{dt^2}=-\frac{l}{g}sin\theta[/math] Simple Harmonic Motion is defined by [math]a=-w^2x[/math] If we assumed the angle to be small, [math]sin\theta=\theta[/math], the pendulum would obey SHM, otherwise it doesn't. An example would be if we increased the angle to [math]\pi[/math]. The pendulum would just drop and not obey any form of SHM. (unless the length is a spring)
  16. Ok then, take an object of mass 7e10kg that has a radius of 10km. There is a good 400m between the object and the schwarzchild radius. That's the area of interest.
  17. Lots of comments about the outside of a black hole and what happens just beyond the event horizon. What happens when the black hole is smaller than the Schwarzchild radius? Is anything transmitted, energy or otherwise between the black hole and its event horizon? What would be its surface temperature then?
  18. There's always one ain't there. ok then, is born, grows, reproduces and dies
  19. Isn't life simply something that is born, grows and dies. A table does not grow, it doesn't die, it remains a table, therefore is inanimate . .. lifeless. A tree grows and can die, as do plants, animals etc. That's my perception of life
  20. No this wasn't to do with refraction. It was 5-6 years ago I picked this book up and I can't remember what its called or who its by, it was just QED stuff. It talked about how light reflects and transmits on front and rear surfaces of a glass block. For example 4% are partially reflected of the front surface, leaving 96% to transmit to the rear surface, which in turn reflects 4%. I was doing A-level physics at the time and so I'm fairly certain it was not relating to basic refraction stuff. It also mentions particle-wave duality and refered to photons as wavicles. It was good because it focused on light itself as a whole, instead of pin-pointing specific areas of physics. I'll see if I can find the book and spend some time reading it, maybe then I can get a better understanding of answering the concepts in my post above.
  21. The answer is so simple yet I can't figure out a way of calculating it algebraicly, unless I'm missing something stupid.
  22. Are you refering to Young's two slit interference experiment alongside the principles of superposition? I can only really look at this in terms of thinking of two speakers punching out sound waves. A compression of air + a compression of air would equal a greater compression of air and vice versa. I find it difficult to imagine how light "cancels" out though. Another interesting comparison with sound is "Beating". If you plot a sine wave for a red wave and a green wave you get beats with the frequency of a yellow wave.
  23. I've heard that the life span of plasma screens are pretty small compared to CRT. That you may have to fork out to get it recharged / repurged. Anyone heard this?
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