Recent content by Physics321

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    Uncertainties in the momentum and kinetic energy of the proton?

    Homework Statement A proton in a tin nucleus is known to lie within a sphere whose diameter is about 2.2 multiplied by 10E-14 m. What are the uncertainties in the momentum and kinetic energy of the proton? Homework Equations delta(x)*delta(p) >= hbar delta(E)*delta(t) >= hbar The...
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    De Broglie wavelength of a neutron

    Homework Statement What is the de Broglie wavelength of a neutron whose kinetic energy is equal to the average kinetic energy of a gas of neutrons at temperature T = 17 K? Homework Equations lambda = h/p = h/mv. The Attempt at a Solution Well first I tried taking the h =...
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    Two slit diffraction, neutron, kinetic energy

    In a neutron two-slit diffraction experiment, the slits are 100 µm apart. If the third diffraction maximum is located at an angle of 2.0x〖10〗^(-7) rad, what is the kinetic energy of the neutrons? Relevant equations: nλ=Dsinθ K=p^2/2m=h^2/(2mλ^2 ) Thus we have then λ=((100x〖10〗^(-6) m)...
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    Two slit diffraction, neutron, kinetic energy

    Yes, I would really like some additional input on this problem as well, if anyone has anything to offer. I have tried all of the steps Yroyathon has done and still have not arrived at the correct answer. Except what I did was do (6.5E-5sin(2^-7))/(3)=lambda. From this I used K=...
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    Telephone communications (easy question)

    Sure, that makes sense as well. Thus: [2(4.02E7 m-6.36E6 m)]/(3E8 m/s) = 0.2256 seconds which makes the comparison as follows: 0.2256 seconds/0.02666 = 8.4621 which simply means, It would take 8.4621 times longer to reach North America from Europe using the satellite method...
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    Telephone communications (easy question)

    Oh that makes sense. So in turn I understand that 2x(4.02E7 m) {for there and back} - (6.37E6 m) {for the radius of the earth} divided by the speed of light. Hence [(2x(4.02E7 m))-(6.37E6 m)]/(3E8 m/s) = 0.2467 seconds. Thus, I am still stuck on how to compare these two times If I...
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    Telephone communications (easy question)

    Homework Statement Telephone connection between Europe and North America can be carried by cable or by the use of a geosynchronous communication satellite. Estimate the time it takes for a signal to travel 8000 km via cable, assuming the speed is close to the speed of light. How does this...
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    A diatomic ideal gas such as air..

    So I searched around and found this one. It relates 2 volumes and an initial temperature.
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    A diatomic ideal gas such as air..

    Are you talking about this equation? I see it relates pressure, volume, and gamma, but not temperature.
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    A diatomic ideal gas such as air..

    A diatomic ideal gas such as air, for which γ = 1.4, expands adiabatically to 40 times its original volume. (a) By what factor does the temperature change? (b) By what factor does the pressure change? I'm not sure how to attempt/approach this one. If anyone has any suggestions, it would be...
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    The pressure sand exerts on a particular area.

    Grains of sand of mass 3.0x10^-3 g each, fall from a height of 0.8 m on a sticky surface at a rate of 50 grains per second per cm^2. What pressure does this shower of sand exert on the surface, assuming that air resistance can be neglected? I'm really not sure what angle to take here. I...
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    Calculating Steam Needed to Heat Espresso from 50C to 80C

    I am having trouble with this question: The temperature of the espresso coffee (mostly water) can be increased by blowing 100 C steam into it. How much steam (in grams) is needed to heat up a 20 cm^3 cup of espresso from 50 C to 80 C? What is the volume of this quantity of steam assuming that...
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