Recent content by sphys4

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    How to find the temperature of a black body?

    It's online homework that i copied and pasted, it's okay though.. thank you for your time and attempting!
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    How to find the temperature of a black body?

    Okay so i found lamba which i got .075, then divided that by b (the constant) and got 25.88 which is still wrong. :(
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    How to find the temperature of a black body?

    Ahh * photons. And yes, this is the problem. Suppose a blackbody emits photons strongly with a frequency near 4 GHz. What is the photon energy? And then i found the value that i stated above (in J), which is correct. The question then asks for the temperature of the black body and that's...
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    How to find the temperature of a black body?

    E=hc/lambda? So i solve for lambda and plug it into my above equation? Does v=4E+9?
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    How to find the temperature of a black body?

    Homework Statement It emits protons with a frequency of 4 GHz, and has a photon energy of 2.65E-24 J. I tried to use the formula lambda=c/f=vT, but i am somehow getting a negative answer which doesn't make sense when trying to find temperature in (K). Any help is greatly appreciated.
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    Calculating Velocity Using Length Contraction Formula in Relativity Theory

    I guess that means i am, so i switch 300 and 445?
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    Calculating Velocity Using Length Contraction Formula in Relativity Theory

    Well L1 is supposed to be the length observed by an observer in relative motion with respect to the object, which would be 445?
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    Calculating Velocity Using Length Contraction Formula in Relativity Theory

    Homework Statement A spaceship moves past you at speed v. You measure the ship to be 300 m long, whereas an astronaut on the ship measures a length of 445 m. Find v. The Attempt at a Solution I tried to substitute my numbers into L1=Lsqrt(1/(v^2/c^2)) and keep getting a negative wrong answer...
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    Frequency of X-Rays: Calculate from Wavelength to GHz

    So what is the speed? Is it the constant c, 3E8? And will using that give me my answer in Hz?
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    Frequency of X-Rays: Calculate from Wavelength to GHz

    Homework Statement X-rays are electromagnetic waves with very short wavelengths. Suppose an X-ray has an wavelength of 0.126 nm. What is its frequency? The Attempt at a Solution I tried (1)/(1.26E-10)=7936507937, which is in Hz, but they want it to GHz, so i converted it and got 7.94 GHz but...
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    What is the Ratio of I1 to I2 for Zero Magnetic Field at Points A, B, and C?

    Well then i would have to use B = ul/2pir? So do i just find that for each of the wires and then add them together?
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    What is the Ratio of I1 to I2 for Zero Magnetic Field at Points A, B, and C?

    Homework Statement Because of the 2 wires in the figure, For what value of the ratio I1/I2 is the magnetic field zero at the point A? point B? point C? Homework Equations http://tinypic.com/r/5otweg/7 The Attempt at a Solution I honestly have no idea where to start with this problem, any help...
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    Magnetic Field Strength Calculation for a Solenoid with Given Parameters

    Homework Statement A 10 cm long solenoid with 241 turns and radius R = 3.00 cm has a current flowing through it of Io = 200 mA. What is the magnetic field strength inside the solenoid (in T)? The Attempt at a Solution So i know i have to use the formula B = (uo)(n)(Io) uo = a constant 1.257 x...
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    Calculating Resistivity: Finding the Area of a Wire

    Homework Statement A wire has a diameter of 1.51 mm and a length of 32.7 m, and is found to have a resistance of 1.5 capital omega. What is the resistivity of the wire? Homework Equations The Attempt at a Solution R=qL/A R=.0051/2=7.55E-4 L=32.7 A = ? How do i find A to...
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