Recent content by erezb84

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    Verifying Diff. Force Equation for System: Can You Help?

    ok, thanks!
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    Verifying Diff. Force Equation for System: Can You Help?

    Homework Statement Hi, i need to write the differencial force equation for the system attached, and i am not sure if what i do is right. when: F- externa power m1,m2 - mass x1,x2 - mas location The Attempt at a Solution This is what i got: for m1: F-k*(x1-x2)-D*(x1'-x2')=m*x1''...
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    Find system rise time with matlab

    Yes.. You are right... Any ideas how can i do it?
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    Find system rise time with matlab

    Homework Statement I need to find a system rise time (from 10% to 90%) using matlab. Is this code right? The Attempt at a Solution sys = tf(num, den); y= step(sys, t); tr1 = max(find(y<0.1)); tr2 = min(find(y>0.9)); rise_time = t(tr2) - t(tr2); Is this seems to be right?
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    Calculating exp(At): Reverse Laplace Transform vs. Matrix Series Method

    daaaam! right, thanks!
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    Calculating exp(At): Reverse Laplace Transform vs. Matrix Series Method

    but s(s+1)-1 is the deteminante.. in oreder to reverse 2*2 matrix i do this: [a b ; c d]^-1 = [d -b; -c a] * 1/det no?
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    Calculating exp(At): Reverse Laplace Transform vs. Matrix Series Method

    this is what i get. but i can't find the reverse transform...
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    Calculating exp(At): Reverse Laplace Transform vs. Matrix Series Method

    Homework Statement I have the following matrix: A=[0 -1; 0 -1] and i need to calculate: exp(At) in several ways, 2 of them are using the reverse Laplace transform and using: I + Ʃ(A^kt^k)/k! i have tried to start the series but i am getting an expression that i can't say which series it...
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    Norton Equivalent Help - Find Equivalent Circuit

    i have tried taking the steps to find the norton source: i have shorted the load (Z) and want to check what current is Iab. tried some KVL,KCL but with no success to get somthing...
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    Norton Equivalent Help - Find Equivalent Circuit

    yes, between a and b.
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    Norton Equivalent Help - Find Equivalent Circuit

    Hi, Need some help in finding Norton eqvivalent for the follwoing circuit: thanks!
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    Engineering Matrix therory - Electrical Circuits

    Theoretic question: is there a way to know if it is no possible to write impedance/admitance matrix (depend on which method we want - volage or currents) just from the circuite connections? Thanks!
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    Engineering Find Thevinin Equivalent for AB - Electrical Circuits Homework

    Homework Statement I need to find the thevinin equivalent for points AB. The Attempt at a Solution I know the Is current is splitting equally between R1 and R3, but doesn't go to R2 because of the dependent current source. so i thought that through: I(R5) = Is and I(R3)=Is/2 so the...
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    Comp Sci Implement Polynom in C++ w/o Linked List

    Ok, Many Thanks!
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    Comp Sci Implement Polynom in C++ w/o Linked List

    In order to make the adding easier i need to save the polynom in this order right? so if i need to add to a given polynom another node (with new coefficient and exponent) i nedd to insert it on the right place?