Recent content by matt72lsu

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    Magnitude of Magnetic Field

    Homework Statement A rectangular loop of wire is moving toward the bottom of the page with a speed of .042 m/s. The loop is leaving a region in which a magnetic field is directed into the page; the magnetic field outside this region is zero. If during the time of 1.5 s the magnitude of the...
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    Energy homework problem help

    Homework Statement The atomic mass of gold-197 is 196.96654 u. How much energy is required to completely separate the nucleons in a gold-197 nucleus? Homework Equations E = 196.96654 u x 931.5 The Attempt at a Solution I did the above calculation and got 1.83e5 MeV but im pretty...
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    Proton distance help

    Homework Statement A proton is released from rest at t=o in a uniform electric field whose magnitude is 2.5e-8 N/C. How far has the proton traveled after .5 s? Homework Equations x = vot + 1/2at^2 The Attempt at a Solution x = 1/2(9.81)(.5)^2 = 1.2 but it says the answer is...
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    Lens Power (diopters)

    Ok cool. Thanks everybody!
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    Lens Power (diopters)

    ok i still don't completely understand, but I come up with 3.1 ???
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    Lens Power (diopters)

    I'm still not sure what I'm doing wrong here. Help?
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    Lens Power (diopters)

    So the only thing I can come up with is .5/.35 = 1.4 (based on what you said)
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    Lens Power (diopters)

    Homework Statement A middle-aged man starts to wear eyeglasses with lenses of 2.0 D that allow him to read a book held as close as 25 cm. Several years later, he finds that he must hold a book no closer than 35 cm to read it clearly with the same glasses, so he gets new glasses. What is the...
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    Images on a retina

    Homework Statement Which forms the larger image on the retina of your eye: a 43 ft tree seen from a distance of 210 ft, or a 12 in flower viewed from a distance of 2.0 ft? Homework Equations none? The Attempt at a Solution I don't really understand how you would go about working...
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    Image Height

    nevermind I found my mistake. thanks for the help though
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    Image Height

    Homework Statement Your friend is 1.7 m tall. What is the height of her image when she is 4.2 m from you? Homework Equations I used di/do and multiplied that by the height of the friend The Attempt at a Solution I did (4.2/3.5)(1.7) but it was wrong. Not really sure what I'm...
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    Focal length / Object height

    Ok I'm getting 2 cm. Could you double-check that please?
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    Index of Refraction

    so would i do 180-110 or something like that? the angle thing is messing me up
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    Focal length / Object height

    Homework Statement An object is located 27.5 cm from a certain lens. The lens forms a real image that is twice as high as the object. b) Now replace the lens used in Part A with another lens. The new lens is a diverging lens whose focal points are at the same distance from the lens as the...