Recent content by xrotaryguy

  1. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    I would imagine that you have started your project at this point since we are so close to the end of the semester. However, I might as well reply any how. The water would have to be kept in with a cork of sorts. I think that it would be best to have a cork that is less dense than water. That...
  2. X

    Understanding Impulse and Conservation of Energy in Bouncing Ball Collisions

    Yeah, and I worked so hard at those images too :P Ok, I'll try conservation of energy. Thx
  3. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    Well, it's really just a 2 litre bottle that is half full of compressed air, and half full of water. The open end of the bottle faced down, and it's cap has a hole drilled in it. The hole acts like a nozzle on a rocket motor. There have to be fins at the bottom of the rocket too. Once the...
  4. X

    Understanding Impulse and Conservation of Energy in Bouncing Ball Collisions

    Oops, I found velocity with a physics equation that doesn't exist. :-D However, using the V=sqrt(2ax) formula, I still get the wrong answer...
  5. X

    Understanding Impulse and Conservation of Energy in Bouncing Ball Collisions

    I don't know why I'm getting the wrong answer on this one. A 5.00kg ball is dropped from rest from 1.20m above the floor. The ball rebounds .700m. What are the magnitude, and direction of the impulse or the net force applied to the ball during the collision with the floor? So I started by...
  6. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    Here's a bit on how to deploy a parachute. This stuff is pretty cool. http://ourworld.compuserve.com/homepages/pagrosse/h2orrecsys1.htm
  7. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    Are we sure that a rubber band isn't a spring? I guess the instructor just doesn't want you to load a spring and fling something up in the air with it. :rolleyes: Any way I think that twisting the rubber band is the best way to go. You could just buy a bunch of rubber band powered air planes...
  8. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    Oh, now that's an interesting idea. But, doesn't that mean the part of the rubber band that is on the outside of the coil will have considerably more tension on it than the windings at the center of the coil? It seems to be like you'd get a pretty good initial torsional force, but after that the...
  9. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    I would guess that a sideways winding would wound along a boom with a tail fin on it. That way, one sructure would be used for two purposes. That'd reduce the mass of the machine. I don't know that the verticle height gained by mass saved would be greater than the height lost by mechanical...
  10. X

    Diving into water / Nonconservative forces

    Haha, well I was kinda thinking I had it right too. I guess I'll look at it again and see if I can hit all the keys right on my calc right this time then.
  11. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    Here you go. I didn't add any dimensions, but you get the idea.
  12. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    this one should go pretty high http://www.qsl.net/k5lxp/projects/Launcher/Launcher.html
  13. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    Ok, I've got it! Build a giant water rocket with spud gun technology. I can't believe that a physics teacher would actually allow a test like this. This is so dangerous. Does he not realize what aspiring engineers are capable of. Any how... Use a 1.5 ft long section of pvc pipe with a cap on one...
  14. X

    Help with Final Project: Build an Object That Jumps Up Mechanically

    Potato Gun A helocopter is a fine ideah. :) Or you could do a potatoe gun. Dry fire a potato that is pointed at the ground. You'll need a portable air tank ($20), a large diameter ball valve ($20 ish I hope :) ), 2ft of 2" dia steel pipe like sewer line or galvanized fence post ($5) and...
  15. X

    Diving into water / Nonconservative forces

    Man, I had such an easy time with the subject matter up to this chapter. Any how, I'm stuck agian. :( Here's the trouble this time.
Back
Top