Recent content by data1217

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    At which times will the ball be at a height of 15 meters?

    S=ut + 1/2 at^2 it should be used in a straight line motion and uniform acceleration.
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    Solving a Mechanics Problem: Deceleration

    but why the derive says so? the v is negative, why not the a is not equal to -g+kv in the derive? is it a more general derive?
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    Solving a Mechanics Problem: Deceleration

    I got a problem with my notes in introduction to mechanics. In the 1st picture, why the deceleration should be " a=-g-kv" instead of " a=-g+kv" ? The air drag should be against the motion. the motion is downward, then the drag should be pointing upward. So I think it should be "positive"...
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    When a battery will no longer produce current

    I think the electric potential of the poles are equal as there are no current produced
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    How does tunneling explain the behavior of transistors in BJT and FET devices?

    Diode is a PN junction BJT is a PNP or NPN type junctions Their working principle is similar. They are based on the different concentration of charge carriers (doping).
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    Projectile Fired Over a Hill: Find H, R, Angle & t_g

    Decompose the velocity as x and y components first. the X and Y components are independent to each other
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    Kirchoffs current law. Someone check to make sure its correct?

    You are right. for the node with Ib and Id entering, Ia leaving -Ia + Ib + Id = 0 -3 + Ib + -1 = 0 Ib =4A
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    Radius of curvature of a Projectile

    v_y ^2= u_y ^2+ 2a_ys Let the upward direction as positive For the y-components and \theta 0 = u^2{ \sin^2{\theta}} -2gh h = \frac {u^2 {\sin^2{\theta}}}{2g} For the \frac {\theta}{2} h = \frac {u^2 {\sin^2{\frac {\theta}{2}}}}{2g}
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    Kirchoffs current law. Someone check to make sure its correct?

    Due to the series configuration, Ic and Id are equal in magnitude but opposite in direction. if Ia = 3A, Ic = 1A, then Id = -1A Ia + Ic - Id - Ib = 0 3A + 1A - 1A - Ib = 0 as a result, Ia=Ib = 3A
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    ReEvaluating real integrals using residue calculus

    1) There are some standard formats/ combinations of functions. 2) Sorry, I am not very clear about this question. 3) Question: I = \int_{0}^{\Pi} \frac{1}{{(a+b \cosx)^2}} dx Answer : I = \frac {ab^2 \Pi}{(\sqrt{a^2-b^2})^3}
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    Finding th value of x and radian when volume is maximum

    You can derivate the given function of volume with respecting to x dV/dx = 0, solve the equation. Then the result follow.
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    Why Is Calculating f(2+h) So Confusing?

    Yes. That's it. f(2+h) = 2+h / 3+h You should notice that h is not equal to -3 or x is not equal to -1 as x = 2+h . something over zero is meaningless.
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