Recent content by nehcrow

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    Simple Inverse trigonometry question

    This is a simple question but I really need to know why: why is the alternate form of arccosh(x) = log(x + sqrt(x^2 - 1)) and not log(x - sqrt(x^2 - 1)) How do I justify the plus/minus sign? I need to know this ASAP, thanks.
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    Amplitude of a simple harmonic motion equation

    if you have the equation: x(t) = Acos(ωt + ϕ) and you have the following information: A 200 g block hangs from a spring with spring constant 10 N/m. At t = 0s the block is 20 cm below the equilibrium position and moving upward with a speed of 100 cm/s. The answers give a short method of...
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    Why Does My Quadratic Equation Not Solve in This Momentum Problem?

    Homework Statement See attached image Homework Equations Momentum equations. Kinetic energy equations. The Attempt at a Solution I attempted to write out the momentum equation and the kinetic energy equation and tried to resolve the two equations (which became a quadratic) but I...
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    Coefficient of friction from a graph

    Is it possible to find the coefficient of friction just by looking at a graph? A velocity-time or acceleration-time graph which models a particle going up a ramp and down a ramp.
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    Energy/rotational mechanics question

    Rotational kinetic energy? Sorry, I'm really lost when it comes to rotational mechanics, I need people to spell it out for me :(
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    Energy/rotational mechanics question

    OK, so kinetic energy and gravitational potential energy. I got the first part correct, Ug = Mg(y - a) but the 2nd part... not so much :\
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    Energy/rotational mechanics question

    Homework Statement Check attached image. Homework Equations The rotational motion formulas Ug = mgh The Attempt at a Solution Have no idea unfortunately :(
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    Need help with an energy-related question

    Sorry to bother you again but you could you mind setting up the equations? I'm still not getting the right answers :(
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    Need help with an energy-related question

    Thanks alot! I get it now... conservation of momentum, why didn't I think of that :P
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    Need help with an energy-related question

    Homework Statement In a fireworks explosion two fragments are ejected horizontallly back-to-back as the shell explodes 200m above the ground. One fragment (A) has a mass of 0.5kg while the other (B) has a mass of 1.0 kg. (a) If the total energy of the system before the explosion is 1.0kJ...
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