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    Calculate Deutron Mass Given Binding Energy

    Can you explain to me how I can add quantities with differing units? If I don't divide 2.2 by c^2, don't I end up with MeV/c^2 + MeV/c^2 + MeV? I was under the impression that you can't add differing units. Or do I have a fundamental misunderstanding somewhere? Thanks, again!
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    Calculate Deutron Mass Given Binding Energy

    Homework Statement The deuteron is a bound state between a proton and a neutron (and the nucleus of the H2 isotope). The binding energy of the deuteron is 2.2MeV. What is the mass of the deuteron? Homework Equations Mp = 938.3 MeV/c^2 Mn = 939.6 MeV/c^2 The Attempt at a Solution...
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    Parallel plate capacitor with a dielectric?

    That really cleared up my questions. Thanks a lot!
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    Parallel plate capacitor with a dielectric?

    If you have a simple circuit with only a battery and a parallel plate capacitor with a dielectric, what exactly happens when the battery is turned on? Also, if the voltage of a capacitor with a dielectric is less than the EMF of the battery, what happens to the rest of the voltage? One...
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    Trigonometric Substitution

    I was messing around proving the area of a circle using trigonometric substitution. However, I ended up with area = -πr^2. In my integral I ended up using trigonometric substitution and setting x = r*cos(theta) However, this yields x = -r*sin(theta)*d(theta). When that's substituted...
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    Question about directional derivatives and tangent planes ?

    Is it possible to find a directional derivative for a point on z = f(x,y) at a point (x,y) in a direction (u1,u2) using the plane tangent to z at (x,y)? If so, how? Thanks!
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    Binary-star system, gravity + centripetal force question?

    Nevermind, got it. It's actually really easy, I just forgot to change kilometers into meters... fail!
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    Binary-star system, gravity + centripetal force question?

    1. In a certain binary-star system, each star has the a mass of 1.36e30 kg, and they revolve about their center of mass. The distance between them is 1.1e8 km. What is their period of revolution in Earth years? 2. gravity = centripetal force (g*m*m)/d^2 = (mv^2)/r 3. I've tried plugging...
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    Energy: Block sliding down frictionless ramp

    Umm, I really appreciate the answer, however, would you care to elaborate how you got it? And yeah, you're correct. (Although there was never any doubt that you wouldn't be :D)
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    Energy: Block sliding down frictionless ramp

    1. In Figure 8-49, a block is sent sliding down a frictionless ramp. Its speeds at points A and B are 1.90 m/s and 2.60 m/s, respectively. Next, it is again sent sliding down the ramp, but this time its speed at point A is 3.85 m/s. What then is its speed at point B? Figure 8-49...
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    Derivitives of functions

    that's exactly how I solved it, however, I got a different answer than the answer key.
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    Derivitives of functions

    I believe that's supposed to be roman numeral one? Clearly I have no idea what I'm talking about, oh well, I'll have to ask about it tomorrow.
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    Derivitives of functions

    I believe I mean f(g(x))^{1}
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    Derivitives of functions

    sorry, that's supposed to be (f of g), meaning f(g(x))
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    Derivitives of functions

    1. Find the value of (f o g)^1 at the given value of x. f(u) = 1-(1/u) u = g(x) = 1/(1-x) x = -1 2. Chain rule... 3. Okay, so the derivitive of 1-(1/(1/(1-x))) is 1. Also, the derivitive of 1/(1-x) = 1/(x-1)^2. So, in theory, shouldn't the answer be 1/4? I've solved this in...
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    Very Simple Forces Question

    Oh! I get it! Thanks a lot!
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    Very Simple Forces Question

    How, exactly, do we know that there is no fireman under the net pulling in the vertical direction? Isn't the vertical pull sin(40)*190N also?
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    Very Simple Forces Question

    Yes, your answer is correct. However, I'm still confused with how you arrived at that conclusion. I solved the vectors (perhaps incorrectly?) and due to direction, all of the forces seem to cancel.
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    Very Simple Forces Question

    Homework Statement Four firefighters hold a square net, one at each corner. Each person exerts a force of 190 N whose line-of-action passes through a point just below the center of the net and makes an angle with the vertical of 50°. What is the net force the firefighters exert on the net...
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