Recent content by Gavandeshaq

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    Volume of 1 mole of Gas at STP

    I understand that the number of molecules in an isolated system will remain the same, no matter what you expand the volume to, raise the temperature to etc. But how can the equation N=P/kT (I'm going to assume you meant uppercase N for number of molecules there, rather than lowercase n for...
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    Charged Particle Moving in Magnetic Field

    An electron is accelerated through 2.4 x 105 V from rest and then enters a uniform 1.7 T magnetic field. What are the maximum and minimum values of the magnetic force this particle experiences? QV = 0.5mv2 F=QvB Basically, I've got a final value from the above equations, but I'm not...
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    Find Displacement Amplitude for 79.8dB Wave

    The highest note written for a singer in a published score was F-sharp above high C, 1.48 kHz, for Zerbinetta in the original version of Richard Strauss's opera Ariadne auf Naxos. The wavelength of this wave is 0.232m. Suppose people in the fourth row of seats hear this note with level 79.8...
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    How Does Laser Impact Affect Missile Speed Change?

    Ok so say for example, the missile is traveling towards the beam, and it perfectly absorbs it. This would cause a change in speed that would decelerate the missile. But because the missile has absorbed the light, it has gain momentum in one aspect. On the other hand, it's slowed down, so it's...
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    How Does Laser Impact Affect Missile Speed Change?

    I came across the equation when looking for an equation that gave me the momentum of a laser beam when energy was a given variable. It so happened that the equation had the correct variables for this situation. Yeah I'm sorry, I think the "of course" was a misunderstanding. I meant a "whoops, of...
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    How Does Laser Impact Affect Missile Speed Change?

    I got the equation from another thread on this forum. Of course it's not, but I only put it like that on this thread to save time, when I calculated it I put 1/c in. And the missile perfectly absorbs the light. (How does the missile absorbing the light give a different outcome to it reflecting it?)
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    How Does Laser Impact Affect Missile Speed Change?

    The laser has a power of 25MW, over 15 seconds this is an energy transfer of 375x10^6J F= 1/c*dE/dt F= 3x10^-8 * 375x10^)/15 This gives a force of 1/12N The missile has a mass of 200kg F=ma: (1/12)/200=4.17x10^-4 m/s^2 That's the deceleration of the missile due to the laser, correct?
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    How Does Laser Impact Affect Missile Speed Change?

    Ah yeah of course, I've forgotten some basic principles here, going to have to work on that. Just needed to know how to get to the correct variables for the equations, think I can figure that out now. Now that my self esteem and confidence have been significantly lowered I feel I can tackle this...
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    How Does Laser Impact Affect Missile Speed Change?

    Because at this moment in time, I'm getting many conflicting sources of data. I'm desperately trying to understand this concept, as my exam looms nearer. One source tells me the E is measured in Joules, which leads me to quantify the laser as a whole. Another now says that it's measured in eV...
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    How Does Laser Impact Affect Missile Speed Change?

    It's the quantum energy of a photon measure in eV, right?
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    How Does Laser Impact Affect Missile Speed Change?

    I understand that the v in this equation represents frequency. I'm used to the equation E=hf and that just threw me for a second. My only qualm is that I have values for f and λ now that don't seem realistic. Obviously here we're dealing with relativistic momentum because photons don't have...
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    How Does Laser Impact Affect Missile Speed Change?

    Ok, so now I'm using the equation p=E/c=hv/c=h/λ. I found the energy transmitted throughout the 15s of the laser shining on the missile. 25MW*15s= 375MJ, sounds like quite a lot to me... Anyway, from here I use the E=hv part of the equation, which gives me a value of 5.7x10^41 for the velocity...
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    How Does Laser Impact Affect Missile Speed Change?

    Homework Statement A laser is used to focus 25 MW of light onto a missile for 15 seconds. If the mass of the missile is 200 kg, determine the speed change imparted to the missile in the direction of the laser beam. Homework Equations E=hf p=h/\lambda F=dp/dt \lambdaf=c F=ma The Attempt at a...
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    Finding current in a dual battery, triple resistor circuit.

    I3*R3 + V2 = Va I2*R2 + V1 + V2 = Va If that's correct, I assume I use simultaneous equations from here?
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    Finding current in a dual battery, triple resistor circuit.

    Is this right? It seemed very simple to work out (although it is the first question on this worksheet). I have a feeling I'm supposed to treat that central resistor as in parallel with both the right resistor and then the left resistor seperately.
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