Recent content by eq123

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    Working on some old exam problems

    thank you for your fast respond :) i couldn't figure anything out for problems 1, 3, 4 :( as for problem 2 .. this is what i did ..when relaxed wnet = ws + wg = ∆k = 0 ws = -wg Fs d = -Fg d Fs = -Fg -kx = -mg k = mg/x = 2(9.8)/(0.06) = 327 N/m when external force is applied ws = -0.5k(x2f -...
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    Working on some old exam problems

    hey everyone .. I've been working on some old exam problems .. i couldn't figure these out :( A 40-g bullet, with a horizontal velocity of 500 m/s, comes to a stop 20 cm within a solid wall. What is the magnitude of the force from the wall stopping it? (Assume this force to be constant) (Ans...
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    What is the Maximum Velocity of Electrons Ejected from Copper by 200 nm Light?

    thank you.. but how can i relate this to the wavelength concept? this is not a homework problem.. it is an old exam question.. i would appreciate any additional information..
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    What is the Maximum Velocity of Electrons Ejected from Copper by 200 nm Light?

    i've been trying to figure out this problem.. The longest wavelength of light that causes electrons to be ejected from the surface of a copper plate is 243 nm. What is the maximum velocity of the electrons ejected when light of wavelength 200. nm shines on a copper plate? the answer is...
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    This problem is killing me [calculation of electron transition]

    i already figured it out.. since the electron is returning to its ground state.. it is releasing energy.. which means that ∆E is negative.. after taking that into consideration.. the answer should be 7.. wow.. it makes more sense to me now! thank you.
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    This problem is killing me [calculation of electron transition]

    this problem is killing me! [calculation of electron transition] i've been trying to solve this problem.. the answer should be 7.. my answer is 0.7 ! What is the value of n_i for an electron that emits a photon of wavelength 93.14 nm when it returns to the ground state in the H atom? my...
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