Recent content by theory.beta

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    Undergrad Understanding Mechanical Work: Ideal Gas and Fixed Pressure

    Hi Philip, Thank you for the reply. However, I still think P is fixed in general, leading W = PV. Let's look at an integral form of ideal gas law. In essence, we have dT = (PdV+VdP)/R; integrating this would give the ideal gas law. But the actual integrated solution as PV = nRT implies either...
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    Undergrad Understanding Mechanical Work: Ideal Gas and Fixed Pressure

    Hi all, I was wondering if I am having a definition problem on mechanical work. Since dW = -PdV (as I was told in class), is it correct to say the pressure is fixed with W = -PV, since dW = d(PV) = -VdP - PdV = -PdV suggests dP = 0? Thanks S.
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    Undergrad What happens when an electron and positron collide

    Just the usual collision/scattering. One of the two: 1. elastic collision (positron+electron coming out, with same of different momentum; lab frame of centre of mass frame) 2. inelastic collision (produces other particles such as photons, and anything else allowed by kinematics; to calculate...
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    Graduate Heat insulating material near abs zero

    hi all, I was wondering if there is any industrial/common type of material (at around temperature of 3K) that can function as bolts/screws or thin sticks. This is to be used in a cryostat and ideally prevent any heat conduction from the material it is attached to during the process...