Recent content by stauber28

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    Grade 11 Question: finding launch angle

    My post was not directed at you frog. I meant he was doing to much work by plugging in numbers too soon. Keep in mind that some people learn better from taking things apart rather than putting them together. Also, would you mind looking at my post titled "Spherically symmetric charge density...
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    Spherically symmetric charge density given electric potential

    Correction E=-dv/dr <-- I am unsure to just have dr=dr or dr = (the derivative of everything in the 1st equations brackets[] ) - I decided to just have it equal dr I then plugged the E value into the difference equation with r = r, and r' = (r+dr). I took the difference and set it equal to the...
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    Grade 11 Question: finding launch angle

    You are doing more work than necessary. Have you learned the range equation yet? This can be used when the initial and final elevation are the same. R = (v02/g)*sin2θ So if you want your range to be 42.. 42 = (342/9.8)*sin2θ sin2θ=(42*9.8/342) 2θ = sin-1(42*9.8/342) θ = 20.86/2...
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    Helicopter Flight and Jet Pack Adventure

    That is higher than the helicopters max height, but remember his acceleration changes to -1 after 5 seconds while the helicopter acceleration stays at -9.8. Powers Max Height is actually 934, he is still climbing when the chopper hits the ground. The (-) initial velocity was incorrect.
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    Helicopter Flight and Jet Pack Adventure

    I believe there is an incorrect negative sign in my last equation. See if you can find it, and try 895.5 for the answer.
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    Helicopter Flight and Jet Pack Adventure

    I'll go through step by step then from the beginning for you. What to find: H1=Height at which the engine shut off V1=Velocity at H1 H2=Maximum Height T=Time for Helicopter to reach the ground V2=Powers' velocity after 5s H3=Powers' Height after 5 s H4=Powers' Height at helicopter impact...
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    Helicopter Flight and Jet Pack Adventure

    I got approx. 239.5 m. There was a mistake in my 2nd equation, I assumed Powers began falling at G as soon as he stepped out, however his initial velocity allows him to continue upward for a while. So you have to calculate where he will be in 5s after stepping out (using a displacement function)...
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    Helicopter Flight and Jet Pack Adventure

    The answer to b is h2. If you solve / insert your values the equations above it will give you the answer.
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    Spherically symmetric charge density given electric potential

    I calculated E using the first equation. E=dV/dr
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    Helicopter Flight and Jet Pack Adventure

    Just use a few displacement functions. 0 = 432 + 72th -.5(9.8)th2 //time for helicopter to reach the ground h = 432 - .5(9.8)52 //height at jetpack turn on h2 = h - 49t -.5t2 //Plug in th-5s and h______________________________________ If everyone is thinking alike, then someone isn't thinking...
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    A Woman Running Towards a Bus Which Pulls away

    Set your initial position to Zero for woman, and initial position to 11 for the bus. Set these two equations equal to solve. Woman d1=0+5t Bus d2=11+.5t2 When both positions are equal she will reach the bus d1=d2 5t = 11+.5t2 10t-t2 = 22 t=5±√3...
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    Spherically symmetric charge density given electric potential

    1. A spherically symmetric charge distribution results in an electric potential of the form What is the charge distribution? 2. Hint: consider the difference in electric field between two values of r Show that the answer is of the form 3. I have attempted several solutions but haven't...
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