Recent content by dave_baksh

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    Gravitation and Antimatter: Does it Matter?

    No, antimatter has mass in the same way that matter does.
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    Speed of light and Time Travel

    From Franz's post above - am I right in thinking that the centrapeital force experienced from loop de looping in a plane (or in any other way) contributes towards time dilation in the same fashion as being in a gravitational field? Because I've never heard that before (my knowledge of special...
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    Mass vs Distance: Does Distance Affect Mass?

    Provided the observer also has mass then the two would be accelerated towards each other at rates proportional to each other's masses.
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    Assistance Needed For Rearranging Equations

    It's a sad indication of high school standards when an A2 student can't rearrange a simple equation. I've always been against the triangle method as it allows students to rearrange equations without understanding what's going on. I'm not blaming you - it's the failing of teachers and an...
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    Horsepower based on distance and speed

    I had a blast at this and would like to post my working, even if just for somebody to tell me why it's incorrect, Use the equation of motion v^2 = u^2 + 2as and rearrange for a. Assume initial speed is 0, s=180m and v=25.8m/s This gives an acceleration of 1.849m/s^2 Now F=ma with...
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    Help with vector kinematics question

    Success! I get the right answers. That'll teach me to set my working out neatly in future to avoid stupid mistakes! Cheers for the pointers dudes.
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    Help with vector kinematics question

    I tried this for funsies and can't get the answer. Any chance of further help? Not sure if the OP got it figured out so I don't want an answer, just a little more guidance.
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    How Can You Calculate the Force of Impact Without Knowing All Variables?

    You also need to know the length of time that the ball is in contact with the ground. The formula for the force exerted is: Force = (mass of the ball) x (speed of the ball)/(time the ball is in contact with the ground) In order that the force is measured in Newtons you must use the...
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    What is the Impact of an Apple Falling on My Head?

    Because the apple sitting on your head isn't experiencing a decelleration. The decelleration of an apple falling onto your head (and being slowed down by your head) is what produces the force which you feel.
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    What is the Impact of an Apple Falling on My Head?

    The force of the impact (impulse) on your head is equal to the mass of the apple multiplied by the rate of change of velocity of the apple with respect to time.
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    Infra-red Electromagnetic waves.

    The small molecules moving around give off energy in the form of infra red photons. This means they have less energy, so move around less, so the temperature of the object drops.
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    Uncertainty Principle and the size of an atom

    gabba> you mean v subscript p in your last line of working
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    Calculating wind pressure against a rigid wall

    If we went a little further back to basics, we might realize that force = pressure TIMES area
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    Why Universe Expansion Doesn't Affect Solar System

    Yeah that's right. That answers the OP's question doesn't it?
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    Why Universe Expansion Doesn't Affect Solar System

    I remember from university that the space between galaxies expands, the galaxies (and their contents) do not
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