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Apr 23 2013 09:57pm
Someone in the class described these as analyzing algorithms, but I'm not sure what they are actually called.
I'll pay fg for this if necessary, 25 fg per problem. I've been told it's really easy if you know anything about math, but since I'm a soft science kind of gal, I look at this stuff and go lolwat.

1. An aircraft is flying level at 10,000 feet above the ground and at a speed of 500 fps (feet per second). It drops a bomb. How far does the bomb go before it hits the ground?
  • How long does it take to hit the ground?
  • How far forward will the bomb travel before it hits the ground?
2. A gun is fired with the initial velocity of 490 fps from shoulder level (which is 5 ft. above the ground) at a target 200 ft. away. The bullseye is also 5 ft. above the ground.
  • How much time will pass before the bullet or the ground (whichever comes first)?
  • What will the drop be after 200 feet?

    Those are the ones that need to be done. However, if you have a knack for this stuff and want to help me with the extra credit, I'll pay an additional 25 fg for that one too.
    A ball is thrown at a 30 degree angle with an initial speed of 50 fps.
    [LIST]
  • How high will the ball go?
  • How far will the ball go?

I'm hoping for 25 fg for each problem.
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Apr 23 2013 10:26pm
looks like straight forward newtonian mechanics. these should be very helpful

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Apr 24 2013 02:23am
The key to doing things kinds of problems is to calculate in only one direction at a time, that is the up/down direction, and the left/right direction (I could describe it more rigorously with terms like linear independent vectors, but I don't think that would do you much good).

Looking at these problems you want to calculate the time it will take these objects to fall to the ground (up/down direction). Once you know that, you can calculate how far the object will travel in the left/right direction in that amount of time.

The extra credit problem is a little harder because the initial velocity is not given cleanly in either direction we are interested it. So you must decompose it (with some basic trigonometry) into the up/down and left/right direction.
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Apr 24 2013 04:42am
These are basic projectile problems, and I will provide a YouTube video that will basically give you an answer to the first question.

I would convert these values to meters:
10000 F would be 3048 meters and 500 FPS would be 152.4 M/S.

You should know that there is an acceleration in the downward direction, as there is gravity (9.8 M/S). There is 0 M/S initial velocity in the vertical direction.

d=V1T + (1/2)at^2
-3048m= (1/2)(-9.8M/S)t^2
-3048m= -4.9t^2
622.0408= t^2
24.9 m/s = t

d= vt
d= 152.4 x 24.9
d=3800.9626 m

(note that I punched all the figures into the calculate at once, so it might be slight off if you calculate from those figures)

In the second problem it seems like the 5ft information is irrelevant, as both sides are above the same level.



For your last problem:
http://www.youtube.com/watch?v=tUUU8ZnlqMU
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