Recent content by IHave

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    Sifting Property (Dirac Delta), please check these

    Homework Statement use the sifting property of the dirac delta function to evaluate the following integrals. a) integral from -inf to inf sin(t) delta(t-pi/2)dt b) integral from 0 to 2 e^(2t) delta(t-1)dt c) integral from 0 to pi e^tan(theta) delta(theta- 3pi/4)d(theta) d)...
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    Solve the following initial value problem (DiracDelta function)

    Homework Statement y'' +4y = 2 delta(t - pi/4) where y(0)=0 and y'(0)=0 Homework Equations Laplace transform Inverse Laplace transform The Attempt at a Solution after applying laplace tranform Y(s)=2e^((-pi/4)*s) / s^(2)+4 as the final answer i have y(t) =...
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    Is this a trick question or is it just that simple? (magnitude and unit vector)

    Homework Statement okay i don't have the exact problem in front of me right now but it went something like this: they gave the force, F, which equaled 500 N. for part a they said to express in terms of a magnitude times a unit vector. for part b they wanted the force expressed in orthogonal...
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    Magnitude and angles of a force

    Homework Statement a force is given by F= 20i - 60j + 90k N. Find its magnitude and the angles it forms with the coordinate axis. Homework Equations F = magnitude of F times the unit vector magnitude is square root (Fx squared + Fy squared + Fz squared) and the unit vector can be...
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    How to Calculate Dot Product of Two Vectors?

    Homework Statement obtain the dot product of the two vectors F= 10i + 6j - 3k lb and B= 6i -2j ft Homework Equations F dot B = FxBx + FyBy + FzBz x is for the x components y is for the y components z is for the z components The Attempt at a Solution F dot B = (60 + -12 + 0) I ended...
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    Calculating Nitrogen Dioxide Levels in Long Beach on a May Day

    108 PSI if anyone was wondering.
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    Calculating Nitrogen Dioxide Levels in Long Beach on a May Day

    thank you so much, i knew i was missing something 'cause the integral itself doesn't find the average. so i was missing the b-a component. thanks i was able to figure it out.
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    Calculating Nitrogen Dioxide Levels in Long Beach on a May Day

    Homework Statement the amount of nitrogen dioxide, a brown gas that impairs breathing, present in the atmosphere on a certain day in may in the city of long beach is appoximated by: A(t) = ((544) / (4 + (t - 4.5)^2) + 28 t is on interval [0, 11] where A(t) is measured in pollutant...
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    What is the average value of the positive y-coordinates of an ellipse?

    Homework Statement Find the average value of the positive y-coordinates of the ellipse x^2/a^2 + y^2/b^2 = 1 I don't know where to begin, please help.
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    What Direction Does the Force on the Wire Point in a Solenoid Setup?

    Thanks, I think I have a better grasp on the concept. So for this problem the force points to the south.
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    What Direction Does the Force on the Wire Point in a Solenoid Setup?

    Quick question on force direction...Please help! Homework Statement A 550 - turn solenoid is 12 cm long. The current into it is 36 A. A 3.6 cm long straight wire cuts through the center of the solenoid, along the diameter. This wire carries a 26 A current downward (and is connected by other...
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    Estimate the magnitude of the torque the large loop exerts on the smaller one.

    Homework Statement A small loop of wire of radius 1.5 cm is placed at the center of a wire loop with radius 20 cm. The planes of the loops are perpendicular to each other, and a 5.0 -A current flows in each. Estimate the magnitude of the torque the large loop exerts on the smaller one...
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    Determine the magnitude of the net force on the loop.

    oh okay, i guess I am still having trouble with determining the direction of the different fields. i was able to figure it out. answer: F = 5.1x10^-6 N
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    Determine the magnitude of the net force on the loop.

    Homework Statement A rectangular loop wire is placed next to a straight wire, as shown in the figure. There is a current of 3.5 A in both wire. Figure: http://www.flickr.com/photos/65980314@N06/6020832477/ Homework Equations F = ((mu(0)*I1*I2) / (2*pi*r)) * L force in terms of...
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    What is the magnetic field strength?

    Homework Statement A 14.2 cm - diameter circular loop of wire is placed with the plane of the loop parallel to the uniform magnetic field between the pole pieces of a large magnet. When 3.10 A flows in the coil, the torque on it is 0.135 m N. What is the magnetic field strength? 2...