Recent content by cuddlylover

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    Relating Point Charges for a Net Zero Force

    If someone could go into more detail on this would be a big help
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    Relating Point Charges for a Net Zero Force

    Point charges q1 and q2 lie on the x-axis at points x = -a and x = +a, respectively. (a) How must q1 and q2 be related for the net electrostatic force on point charge +Q, placed at x = +a=2, to be zero? (b) Repeat (a) but with point charge +Q now placed at x = +3a=2. Can someone help me...
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    Polaroid sheets and the law of malus

    Me to lol i get the feeling that was not my degrees button i just hit :)
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    Polaroid sheets and the law of malus

    28%?
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    Polaroid sheets and the law of malus

    (cos(50)^2)/2 Is that not right?
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    Polaroid sheets and the law of malus

    Unpolarised light passes through two Polaroid sheets. The axis of the rst is horizontal, and that of the second is 50 above the? Do i have this right. I am using law of malus I=I0 cos2θ Im getting 47% but i don't know if that's right. If someone could help that would be awesome thanks.
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    Help Solve Lens Projector Distance Puzzle!

    I posted this somewhere else and someone posted that but could not see how they got to it :)
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    Help Solve Lens Projector Distance Puzzle!

    Or should it be 3.9mm i am a bit lost here i think lol.
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    Help Solve Lens Projector Distance Puzzle!

    I have this in my home work and i am not 100% on if i have it right or not A converging lens with a focal length of 25 cm is used to make a slide projector. If the image is to be projected onto a screen 10m away, how far should the lens be located from the transparency? I did it like...
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    Calculating Pressure w/ Nitrogen Molecules: Where to Start?

    If 61022 nitrogen molecules with an rms speed of 450m=s occupy a volume of 2103 cm3, what is the pressure? Nitrogen molecules have a mass of 28 amu. I have been giving this but have no idea where to start. Can somebody point me to a starting point so i can have a go at it.
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    Ideal Heat Engine: Input Temp Change, Exhaust Temp Change?

    How would i write and do this algebraically?
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    Ideal Heat Engine: Input Temp Change, Exhaust Temp Change?

    I worked out the original efficiency and then times the original efficiency by input temperature 2 to get the exhaust temperature 2. Is that not right how would you do the working? I was thinking it was incorrect base on a feeling there is a carnot limit of about 10C but i mite be wrong :)
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    Ideal Heat Engine: Input Temp Change, Exhaust Temp Change?

    An ideal heat engine operates with an input temperature of 327C and an exhaust temperature of 27C. If the input temperature is lowered to 227C, by how much must be the exhaust temperature be lowered to maintain the same eciency?Im using η= 1-(tc/th) that works out to 1-(300k/600k) = 0.5 then...
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    How Do You Calculate Final Pressure in an Expanding Gas Scenario?

    Still not getting it so if i have p1.v1/t1 = p2.v2/t2 i can just more them over to make p1.v2/t2 and that will give me p1?
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    How Do You Calculate Final Pressure in an Expanding Gas Scenario?

    Thanks for that. You where right i was using the combined gas law. Are you able to give me a little more info on "If you wanted to find P on the right hand side, take T then V to the other side ;)" Sorry I am a comp sci major being made to do this :)