Recent content by Aftermarth

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    Help with Limit: ((sin a)(sin 2a))/(1- cos a) as 'a approaches 0

    well we can't solve it for you but you have to think of limits like this (from what i remember) sub in 0 and see what you get, and i think you will find its undefined at zero, so then you need to think what the curve is doing as it approaches zero. Put small numbers in and see where it is going :)
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    Preventing Shockwaves from Supersonic Flight

    Oki well ill start with a little background so you know just about me :) I am studying aero engineering in Sydney Uni and second year student so i haven't really hit all the Flight Mechanics and aerodynamics yet that comes next year but i was talking in a laboratory with a 4th year student (we...
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    Graduate What Do Dimensions 5-14 in String Theory Really Mean?

    ok just chucking another idea out there... in maths I am doing Vector Calculus and Linear Mathematics. We do simple equations like finding spans and what not But in the R3 plane, when you find a span of two linerly independent vectors, it is a plane in 3D space. Given a R4 plane, when you find...
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    Calculating Delta h for a Projectile Fired at 50 Degrees without Air Resistance

    that is what i got so now subtract the linear from the parabola
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    Finding Velocity and Height of a Kicked Ball

    ill get back to you asap for now i need to go to my Dynamics class good luck if u need sleep go get it.. u will think better when you are rested :)
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    Calculating Delta h for a Projectile Fired at 50 Degrees without Air Resistance

    y = Vy*(t) - (1/2)gt^2 u have Vy i take it already you know t g = 9.81m/s^2 sub it in (that is the parabola equation) for the linear one g = 0
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    Finding Velocity and Height of a Kicked Ball

    sounds good to me
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    Calculating Delta h for a Projectile Fired at 50 Degrees without Air Resistance

    ok how did u get ur answer for the parabola?\ you had 2.13m above and its changeD?
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    Calculating Delta h for a Projectile Fired at 50 Degrees without Air Resistance

    okies u got to post yours first cause I am not allowed to give u the answer but :)
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    Finding Velocity and Height of a Kicked Ball

    haha poor you with this teacher :( to reach the plane of the fence you need to find the time (in seconds) to travel the necessary horizontal distance
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    Calculating Delta h for a Projectile Fired at 50 Degrees without Air Resistance

    this straight line... if it is the path of the shell with a=0 then yes that is right
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    Calculating Delta h for a Projectile Fired at 50 Degrees without Air Resistance

    you will only need Vy it seems here y = Vy*(t) - (1/2)gt^2
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    Calculating Delta h for a Projectile Fired at 50 Degrees without Air Resistance

    i think you are on the right track... i don't quite understand the question but ill try give you a hand its projectile motion so u need those equations and you are dealing in the y direction only... have you broken up the initial velocity?
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    Compressed Air Bottle Rocket (Variable Mass)

    ok. here is an update on my progress... Thrust = \dot{m}v where v = (v - v_{0}) and \dot{m} = \rhoAV using the gas laws (PV = nRT) and Boyle's Law (\rho = (MP)/(RT) along with Pressure/ Temperature = constant T(inside bottle) = 654/T = 101.325/293.15 (NOTE - i have assumed the...
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    Compressed Air Bottle Rocket (Variable Mass)

    Homework Statement I need to find the maximum distance a rocket (which is actually a bottle filled with compressed air to 654kPa) can travel when the exhuast nozzle is 22cm (and can be changed to any smaller size if needed). Neglect air resistance. The bottles original mass is 50g...