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    Prove that 5^(2/3) is irrational

    Homework Statement Prove that 5^(2/3) is irrational Homework Equations The Attempt at a Solution I tried writing a proof but that is not getting me any where. This is what I did so far - Show that 52/3 is irrational Proof: Suppose that 52/3 is rational: 52/3 = a/b...
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    Le Chatelier's principle

    Homework Statement Which process, the formation of the chloro complex, or the formation of the aquo complex, is endothermic? Co(H2O)62+ (aq) + 4Cl- <---> CoCl4 + 6H2O (l) Pink ----------------------------- Blue The Attempt at a Solution The reaction above is endothermic because it turned...
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    Rocket Propulsion - Varying mass

    :blushing: I got the answer! o:)
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    Rocket Propulsion - Varying mass

    Homework Statement A rocket at rest in space, where there is virtually no gravitational force, has a mass of 2.55 * 105 kg, of which 1.81*105 kg is fuel.The engine consumes fuel at the rate of 480 kg/s and the xhaust speed is 3.27 m/s. The engine is fired for 250 s. Find the thrust of the...
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    Find distance for gravity to do only -4 J of work

    Thank you guys :D I'll be back with another problem soon ... hahahah xD ^-^
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    Find distance for gravity to do only -4 J of work

    the component will be sin?? should it be?
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    Find distance for gravity to do only -4 J of work

    the weight component that acting on the mass
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    Find distance for gravity to do only -4 J of work

    so the mass is going to the opposite direction of force ...
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    Find distance for gravity to do only -4 J of work

    I know this is wrong because there's no way the answer can be this simple ... W=F.d -4 = mgsin30 * d d = -4/20sin30 d = -.4 .4 to the left is that even righttt?
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    Find distance for gravity to do only -4 J of work

    Homework Statement http://img137.imageshack.us/img137/9280/43448180.jpg [Broken] find distance for gravity to do only -4 J of work Homework Equations [PLAIN]http://buphy.bu.edu/~duffy/PY105/12m.GIF Wg = mgX The Attempt at a Solution Can anyone help me from the first stepp
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    Spring force, find the speed at equilibrium

    can you give me hints on the other three questions too
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    Spring force, find the speed at equilibrium

    A .50 kg block sliding on horizontal frictionless surface is attached to one end of a horizontal spring (with k = 500 N/M) whose other end is fixed. The block has a kinetic energy of 20J as it pass through its equilibrium position (the point at which the spring force is zero.) what is the speed...
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    Heat of Reaction

    I did a calorimetry lab and here's my result [PLAIN]http://img230.imageshack.us/img230/2953/fullscreencapture111420.jpg [Broken] I'm supposed to find the heat absorbed by the water in the calorimeter, assuming the density of the solution to be 1.0 g/mL I kniow I have to use the equation...
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    Find Muzzle speed

    Homework Statement Find the muzzle speed of a gun whose maximum range is 24.5 km. Homework Equations R = V02sin2angle/g The Attempt at a Solution How do I find the angle? Also can you check what I did wrong in this one? A projectile is fired at a speed of 840 /sec at an angle...
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    Vector problem

    Thanks but I meant like the exact angle ... the mathematical way thank you :D
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    Vector problem

    So suppose we have to go to a specific direction, say 300 miles west, but there is a wind blowing at 45 mi/hr .. how do I know what direction I should travel. And also whats the difference between ground speed and airspeed?? Sorry, I dont have a attempt because I dont know how to find the...
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    Collison question

    My attempt http://oi56.tinypic.com/os6dec.jpg Please help me :(
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    Collison question

    Kinematics Collison question Homework Statement The engineer of a passenger train traveling at 84 m/s sights a freight train whose caboose is 480 meter ahead on the same track. The freight train is traveling in the same direction as the passenger train with a constant velocity of 60 m/s. The...
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    Acceleration-velocity-position graph~

    but I still don't get how I draw it in the graph
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    Acceleration-velocity-position graph~

    How do I draw a velocity vs time graph and a position vs time graph if I'm a given a acceleration vs time graph ? Thank you :D
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    Find Velocity and acceleration

    for A, x=at^2/2 how do I find a?? Thanks though :D
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    Find Velocity and acceleration

    A particle starts from the origin at t = 0 and moves along the positive x axis. A graph of the velocity of the particle as a function of the time is shown in Fig. 2-43; the v-axis scale is set by vs = 7.00 m/s. (a) What is the coordinate of the particle at t = 5.0 s? (b) What is the...
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    Find proportions when there are 2 variables

    Thank you so much for the help :)
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    Find proportions when there are 2 variables

    a is proportional to square root of (b *t2) a is proportional to 1/c3 a is 5, when b = 9, t = 2, c = 3 Find a' when b'=25, t'=2, c'=5 My attempt: = (25 root 5/12 root 3) 5 I think my steps are wrong, can someone help me!?
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