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    Completing nuclear reactions

    Homework Statement Complete the following nuclear reactions, assuming that the unknown quantity signified by a question mark is a single entry. Use the following table for your answers: 0 = gamma, 1 = p, 2 = alpha , 3 = n. (a) 20X43(alpha,?)21X46 (b) 4X9(?,n)6X12 Homework Equations...
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    Finding the binding energy for lithium

    Oops, sorry I know I typed the formula wrong on here, but I did it the correct way on my homework... It's still telling me my answer is incorrect. :/
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    Finding the binding energy for lithium

    Homework Statement Find the binding energy (in MeV) for lithium 3Li8 (atomic mass = 8.022486 u). Homework Equations Binding energy = (#p)(mass proton) + (#n)(mass neutron) - (mass nuclei*c^2) The Attempt at a Solution mass proton = 1.007825 mass neutron = 1.008665 Binding energy...
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    Determining the number of photons that reach the earth

    Oh wow, I never knew I could write my answers that way on this program. haha thanks!
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    Determining the number of photons that reach the earth

    The program I enter my homework answers into doesn't let me have that many decimal places in my answer though (we have to write it out long, it doesnt let us put x10^21), so I was assuming I must've done something wrong.. :-/
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    Determining the number of photons that reach the earth

    Homework Statement Light is shining perpendicularly on the surface of the earth with an intensity of 910 W/m2. Assuming all the photons in the light have the same wavelength (in vacuum) of 668 nm, determine the number of photons per second per square meter that reach the earth. Homework...
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    What angle is subtended when using this 270-diopter objective?

    Ohh, I was making it harder than it should be. Thank you very much!
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    At what angle does the light leave the glass

    Homework Statement The drawing shows a rectangular block of glass (n = 1.52) surrounded by a liquid with n = 1.79. A ray of light is incident on the glass at point A with a 30.0° angle of incidence. At what angle does the ray leave the glass at point B...
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    What angle is subtended when using this 270-diopter objective?

    I don't really understand what this means.. how are you saying I would go about solving this with that in mind?
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    What angle is subtended when using this 270-diopter objective?

    Homework Statement An anatomist is viewing heart muscle cells with a microscope that has two selectable objectives with refracting powers of 140 and 270 diopters. When she uses the 140-diopter objective, the image of a cell subtends an angle of 3.7 x 10-3 rad with the eye. What angle is...
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    Determine image distance relative to lens

    It's telling me that answer is incorrect.. I guess I'll try the -12.547 next
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    Determine image distance relative to lens

    Ok so I took 1/13.487 + 1/i = 1/-6.5 and I solved for i and got -4.386 cm. Is this correct, or should I have used -13.487 and got -12.547 as my answer?
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    Determine image distance relative to lens

    Homework Statement Two identical diverging lenses are separated by 13 cm. The focal length of each lens is -6.5 cm. An object is located 3.0 cm to the left of the lens that is on the left. Determine the final image distance relative to the lens on the right. Homework Equations 1/i + 1/o...
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    At what angle does the light leave the glass?

    Nevermind, I got it :] 53.13 degrees is the answer. Thanks!
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    At what angle does the light leave the glass?

    Ohh, is this right then..? sintheta2 = (1.6) sin30/1 theta2 = 53.13
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    At what angle does the light leave the glass?

    Homework Statement The drawing shows a rectangular block of glass (n = 1.52) surrounded by a liquid with n = 1.60. A ray of light is incident on the glass at point A with a 30.0° angle of incidence. At what angle does the ray leave the glass at point B...
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    Concave mirror - finding object and image distance

    so I tried saying image distance = 50.2 + object distance substituting that into 1/object distance + 1/image distance = 1/f I got object distance = -620.65 cm then image distance would = -620.65 + 50.2 = -570.45 cm This is incorrect... Have I done this right, and the 620.65 simply...
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    Concave mirror - finding object and image distance

    Can anyone help me figure out if I'm even on the right track?
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    How do I find the height of the image?

    Homework Statement A 1.80-cm-high object is situated 19.7 cm in front of a concave mirror that has a radius of curvature of 12.2 cm. Calculate (a) the location and (b) the height of the image. Homework Equations f=1/2R 1/image distance + 1/object distance = 1/f The Attempt at a...
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    Concave mirror - finding object and image distance

    Homework Statement A concave mirror has a focal length of 27.2 cm. The distance between an object and its image is 50.2 cm. Find (a) the object and (b) the image distance assuming that the object lies beyond the center of curvature. Homework Equations f=1/2 R 1/object distance + 1/image...
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    Finding minimum angular speed

    Awesome, got it! 535.79. Thanks for the help! :]
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    Finding minimum angular speed

    I took 2.333x10^-4 and multiplied that by 8 to get .0018664 rev/s but that answer is incorrect
  23. P

    Finding minimum angular speed

    Oh, sorry I meant 2(35000)/3x10^8 = 2.333x10^-4 do I then just divide that by 8 to get 2.91x10^-5 ?
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    Finding minimum angular speed

    Homework Statement The figure illustrates Michelson's setup for measuring the speed of light with the mirrors placed on Mt. San Antonio and Mt. Wilson in California, which are 35 km apart. Using a value of 3.00 x 108 m/s for the speed of light, find the minimum angular speed (in rev/s) for the...
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    RCL circuit containing only a capacitor, inductor, and generator

    WOW. haha someone answered this on my more recent post. The answer is -.841... the pi/2 had to be subtracted instead of added. !!!
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    RCL Circuit - Problem due at 11 PM EST tonight, have been working on it for days!

    Oh wow... I can't believe that was it. It was too late for full credit, but now I know that for my test tomorrow. Thanks! :D
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    RCL Circuit - Problem due at 11 PM EST tonight, have been working on it for days!

    1. Homework Statement A series RCL circuit contains only a capacitor (C = 8.46 μF), an inductor (L = 6.01 mH), and a generator (peak voltage = 77.4 V, frequency = 2.45 x 103 Hz). When t = 0 s, the instantaneous value of the voltage is zero, and it rises to a maximum one-quarter of a period...
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    RCL circuit containing only a capacitor, inductor, and generator

    Ok, that's what I'm getting right now too.. But it's still incorrect. :[ Anyone else wanna take a shot at this?? Thanks so much for your help Delphi!
  29. P

    RCL circuit containing only a capacitor, inductor, and generator

    Please help! Somebody! This problem is due tonight and I've been struggling with it for 3 days now and can't figure out what I'm doing wrong :[
  30. P

    RCL circuit containing only a capacitor, inductor, and generator

    Here are my calculations (using 92.5 for now). The final answer is incorrect still: instantaneous value of voltage = 27.77 V X of L=2pi(2450)(.00601)=92.5 Ohms X of X=1/(2pi(2450)c) = 7.678 Ohms Z=square root(0^2 - (92.5 - 7.678)^2) = 84.822 I0=V0/Z = 27.77/84.822 = 0.32739 A...
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