Recent content by alevis

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    Is there a better way of solving this first order linear differential equation?

    3y'+2y-2sin(3x)+2e(-3x)+x3+4=0 Variables x - independent y - dependent Attempt at a solution I rewrote the equation in form dy/dx+P(x)y=Q(x) and used an integrating factor of \mu(x)=ke(2/3)x with P(x) = 2/3 and Q(x) = 2sin(3x)-2e(-3x)-x3-4 Since y(x) =...
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    Windows that only absorb infrared light

    What are some of the windows or materials that are used to only absorb the infrared spectrum of light passing through the material?
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    Calculate the flux (J) Between points x and y

    The diffusion of Ni in FCC Fe. There is 0.3 atoms % of Ni in a solid solution in FCC Fe @ point x. Point y is 1 mm away and has 0.2 atoms % of Ni within the solid solution. Temperature = 1000° C, D = 2ε-16M2/s Calculate the flux (J) between points x & y. Radius of Fe atom = 0.13 nm @...
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    Find the wavelength of the sound.

    Two speakers , each producing a pure tone of 1000Hz, are separated by 4m and are placed against one wall of a 15m wide room. You walk along the opposite wall of the room and hear the locations of the maxima and minima interference patterns a.)Find the wavelength of the sound. b.)Find the...
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    The sagging effect and angular speed.

    Homework Statement Does anyone know anything about the sagging effect of a object with mass m rotating in a circular path at an anle of "theta" below the horrizontal? How do you find the theoretical angular speed the the object is rotating at R revs/d in t seconds at an angle of "theta"...
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    What is the coefficient of kinetic friction between the block and the incline?

    Homework Statement A 2.00-kg block situated on a rough incline is connected to a spring of negligible mass having a spring constant of 100 N/m. The block is released from rest when the spring is unstretched, and the pulley is frictionless. The block moves 20.0 cm down the incline before coming...
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    Show that the initial speed is vi = sqrt 2gL(l-cosθ).

    Homework Statement An object of mass m is suspended from the top of a cart by a string of length L. The cart and object are initially moving to the right at a constant speed vi. The cart comes to rest after colliding and sticking to a bumper, and the suspended object swings through an angle θ...
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    How Do You Calculate the Force Exerted by Water on a Sled?

    Homework Statement Yhou built a water slide . A rider on a small sled, of total mass 80.0 kg, pushed off to start at the top of the slide (point A) with a speed of 3.0 m/s. The chute was 10 m high at the top, 55 m long, and 0.50 m wide. Along its length, 725 wheels made friction negligible...
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    With what minimum speed must Jane begin her swing in order to just make it to Charlie

    Homework Statement Vernie, whose mass is 45.0 kg, needs to swing across a river filled with crocodiles in order to rescue Charlie,whose mass is 75.0 kg. However, she must swing into a constant horizontal wind force on a vine that is initially at an angle of θ with the vertical. The width of...
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    Calculate Min Initial Kinetic Energies for Javelin, Discus, Shot Throws

    Homework Statement The masses of the javelin, discus, and shot are 1.0 kg, 2.0 kg, and 8.0 kg, respectively, and record throws in the corresponding track events are about 98 m, 75 m, and 25 m, respectively. Neglecting air resistance, (a) calculate the minimum initial kinetic energies...
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    How Can Vernie and George Swing Across the River Despite the Wind?

    Homework Statement Vernie (mass of 50.0kg) needs to swing across a river to rescue George (mass of 80kg). She must swing into a constant horizontal wind force F ona vine that is initially at an angle of O with the verticle. The width of the river between them is 50.0m. The force of the wind...
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    What is the speed of a ball released at the bottom of a vertical circular path?

    Homework Statement A pitcher rotates a 2kg ball around a verticle circular path of radius 1.2m. he exerts a 50N force directed parallel to the motion of the ball around the completer circular path. The speed of the ball at the top of the circle is 20m/s. If the ball is released at the bottom...
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    Can a Dual Machine Setup Improve Efficiency in PV Energy Conversion?

    I'm working on a protoype that uses energy from the sun (PV cells) to convert potential energy into electrical energy . This is the basic structure. A weight is initially attached to the chain. (The chain can only hold 12 pounds) The motor(s) drive the weight up during the day and then after...
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    Energy, Power, Work related question

    This isn't the actual problem given in the assignment. I've twisted it a bit because I want to see were I specifically go wrong in my calculations. [b]1. A pitcher rotates a 0.25kg ball around a vertcal circular path of radius 0.6m before releasing it. The pitcher exerts a 50N force directed...
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