Recent content by Steve143

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    The effects of the alpha, beta and gamma radiation on humans

    I have had a great deal of trouble finding sources that are specific as to how exactly radiation damages the body, it usually just says what damage radiation causes but not how it causes it, so I have compiled what I have found and I want to know if it is accurate and to fill in sequence of...
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    The components of atoms and their effects on its properties

    I have a physics book that says the electrons orbiting an atom are responsible for the physical and chemical properties of that atom. And yet I have managed to find another source which says the number of neutrons can affect the "Density (mass/volume), boiling point, freezing point, and the...
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    Electricity generation - simple bike dynamo - can anyone explain this design?

    I see, so the rotating magnet is not strong enough to power the lights on its own which is why the iron core is needed. However the iron core and the wires are not moving moving relative to each other (From the picture it looks like the rotating magnet spins but everything else remains in...
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    Electricity generation - simple bike dynamo - can anyone explain this design?

    http://img404.imageshack.us/img404/9523/dynamos.jpg I understand that when the rotating magnet spins, current should be induced in the coils which powers the lights. So what is the point of the soft iron core? The rotating magnet should magnetise it because it is near it, and it should...
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    Measuring the pressure of a gas

    http://img526.imageshack.us/img526/8780/pressurew.jpg I worked out that the pressure difference is 1000 pascals For part b the book says the pressure of the gas is 1000 pascals but shouldn't it be 1000 pascals + 100,000 pascals (atmospheric pressure) making the pressure of the gas 101,000...
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    Water waves - is this reflection, or refraction, or both?

    The way I'm interpreting it like this: when the slide is flat on the bottom of the tank the wavelength is reduced. (as far as I know this is because the wave touches the bottom and is probably reflected off it) When the slide is at an angle the wave is refracted. I think of sea waves, the...
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    Water waves - is this reflection, or refraction, or both?

    http://img42.imageshack.us/img42/9712/refractionk.jpg Now my understanding is that water slows down when it goes over a shallow area because the ground under the shallow water is interfering with the wave. When this happens the wave becomes more transverse which I guess is due to reflection as...
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    Underanding voltage and electron's energy loss

    Oh, I think I see what you mean for the second image. I took the current as 1A but that circuit can't exist unless it is 0.5A which makes each resistor eat 50V. I think the previous examples I mentioned can't exist in the real world then I think I understand this now, thank you. The only thing...
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    Underanding voltage and electron's energy loss

    For the second post I think: Before A: 100 volts After A: 100 - (100 * 1) = 0 Before B: 0 volts After B: 0 volts Before C: 0 volts After C: 0 volts For the third post: It lost no voltage at A so no resistance It lost 4 volts at B so 4/1 = 4 ohms It lost 4 volts at C so 4/1 = 4 ohms It lost 4...
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    Underanding voltage and electron's energy loss

    hello, i keep getting conflicting information on these and it confuses me 1) First my book says "In series circuit the voltage supplied by the cell is "shared" between all the components, so the more bulbs you add to a series circuit the dimmer they all become." If you have a circuit...
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