Recent content by discombobulated

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    Real (non-ideal) op-amps - textbook query

    Homework Statement Hello, I'm studying real op-amps and looking the inverting amplifier circuit for a non-ideal op amp model. I'm confused as to where one of the equations from the assumption of zero output current came from, as I get a slightly different one. I've attached the circuit...
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    Understanding Bulk Modulus: Explaining the Relationship with Pressure and Volume

    Homework Statement My textbook says, delta V = [-3V delta p (1 - 2c)] /E where, delta V = change in volume delta p = change in pressure c = poisson's ratio E = young's modulus Taking the limit as delta p tends to zero, we can write the bulk modulus K as, K = -V dp/dV but I'm not...
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    Deriving Laplace Transforms

    Homework Statement Derive the Laplace transform of the following functions, using first principles 3d) u(t - T) \} = 0, \ t<T \ (= 1, t>T) 3e) f(t) = e^{-a(t-T)}u(t-T) Homework Equations see above The Attempt at a Solution I know I need to derive the transform using by integration...
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    Frequency response function

    Homework Statement The relationship between the input voltage V(t) and the output voltage across a resistor VR(t) is:- CR dVR /dt + VR = CR dV/dt Circuit diagram of a capacitor and resistor with VR(t) in series across V(t) 1. Show that the frequency response function G(iw) (w= omega)...
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    Vectors: Solving a Trajectory on the x-y Plane

    thanks, so do i split it like this, d2x /dt2 = 3 and d2y /dt2 = -1 and then when I integrate to get x and y, put it back into i and j form?
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    Vectors: Solving a Trajectory on the x-y Plane

    [SOLVED] vectors - Homework Statement At time t = 0 two forces f1 = (i + j) and f2 = (2i - 2j) start acting on a point body of unit mass lying stationary at the point (1,2) of the x,y plane. Describe the trajectory r(t) of the plane. Homework Equations F = ma a = d2x/dt2 The Attempt at a...
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    Determining Best Value of k for Compound Pendulum

    Homework Statement I have calculated the value of the radius of gyration, k for a bar (and moment of inertia) and got three different values from three different methods. Now i need to determine which is the best value. I'm confused about how to do this, and how do i get the %uncertainty for...
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    How to Solve Simultaneous Equations with Logarithms

    ok I'm sorry for not setting it out clearly enough. What i meant was: log 9 2 = 1/4 p which according to my textbook is correct don't worry I've managed to work out b) as well if log 9 2 = 1/4 p then logq(8q) = logq (23q) so logq(8q) = 3/4p +1
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    How to Solve Simultaneous Equations with Logarithms

    I need some help with this please! 1. given p=logq 16, express in terms of p: a) logq 2 b) logq (8q) this is what i got: a) p= logq16 = logq22 = 4logqqq =1/4 p b) p=logq16 =logq8 +logq q =logq23 + 1 =3logq2 +1 ...?? Also can someone please help get me started on these...
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    Calculate the speed with which the ball hits the ground

    Thanks, so s=1 then I worked out t = 1.82 by using the quadratic equation to solve and finding the difference. I think i need to use v2 =u2+2as for part b, but which value of s should i use? I tried 2m but then i got v=6.26 whichis wong as the correct answer is 11.8.
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    Calculate the speed with which the ball hits the ground

    I need some help with this mechanics question please, A ball is thrown vertically upwards with speed 10ms/s from a point 2m above horizontal ground. a) calculate the length of time for which the ball is 3m or more above the ground. b) calculate the speed with which the ball hits the...
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    Isotopes of an element differ in physical properties

    i think it's because neutrons have no charge therefore have no effect on chemical reactions.
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    Projectile Motion Ball Problem

    have you tried using v2= u2+2as ? I think rearranging that for u should work.
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    Equations and Tangents for Curve C at Point P

    oh wait i remembered i need work out c, by using P(1,4) Thanks for your help!
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    Equations and Tangents for Curve C at Point P

    do you mean i have to integrate dy/dx = (3x-1)2 for b) to get : 3x3 - 3x2+x +c ?
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