How to create a small metalic ball such in bearing ball?
117172
mikempg4 doesn't care. He seems a bit bitter about life. You should read some of his other answers. They're pretty funny.
137583
I've never constructed a double helix before, but try using straws with wooden skewers run through them [to act as stabilizers] and spray-painted styrofoam balls.  I know that styrofoam balls aren't actually household items, but you can pick them up pretty easily at a local arts and crafts store.  \n\nIf the teacher doesn't mind, I suppose you could use apples and oranges...  ^^\n\nAnything that is porous and easy to skewer ought to work.  Like an eraser.
855038
increasing steel volume would increase ammount spilled. the steel ball becomes bigger and there is less volume left for mercury=> more spilling. so it should be +ve: \nChange in Volume = mercury(B*V*changeT) "+" steel(B*V*changeT) - brass(B*V*changeT)\n\nActually, contrary to what I thought before, you don't need to convert B_brass to per-area beacuse when solid sphere expands it's surface expands in the same ammoun as hollow sphere (i did derivation to prove it, but it's long so im not gonna post it).\nanswer= 1.1736 x10^-6 m^3\nif you have questions email.
882835
Probably carbon latice structures, like buckeyballs or nanotubes.  These could then contain the smaller compounds that are doing the desired work.
949238
u can  take rod shaped plastic pipe of different sizes & pingpong balls at sides. cover them with clay to give them shape of a bone, then use  thin elastic rubber ( which are used in rubber band, thin white in color) use many of them  as muscle fibre by attaching them to bone
1168507
Here is one example...the bouncing ball. Just google that in and you get a bunch of results.
381672
if you are trying to build a model - i would recommend either a playdo type creation or if you wanted to be fancy - use a jello mold.\n\nJello mold you make the mini components first and let them harden.  then put them in place in and outside of your 'membrane' and fill in with a clear jello (knox).  The clear represents your axon and cell membrane with your multicolored preformed pieces acting as your pump, na, and K+\n\nhave fun!
1173286
Make the flow in front of your object turbulent by sending something solid right in front of it (like "drafting" in NASCAR) or by putting a rough shape on the object (like dimples on a golf ball).\n\nYou could also heat it up, but that's not very practical in most cases.
612302
You could build a set of fluid armor as seen in the Matrix movie.\n\nA simple magnetorheological fluid can be home-made out of small magnetic particles mixed with mineral or vegetable oil. Iron filings do not work well; they are too big. Good sources for small magnetic particles are:\n\n* magnetic inspection powder from welding shops\n* particles from burned steel wool (after mortar and pestle)\n* particles scraped from the surface of video tapes\n* particles "mined" from sand with a plastic bag and a magnet (see external links)\n\nThese fluids are not very stable, however. The particles will tend to clump and the fluid properties will be lost quickly. Fluids created for professional purposes use emulsifiers to suspend very small oily (octane or kerosene) magnetic particles in water. The particles are very fine; less than a micrometre in diameter.
557989
You can't. It depends on which way the diameter is turned in the circle. There are an infinite amount of solutions. Tell your teacher to be more specific.\n\ntosmith
674234
i'd try a cotten ball and rubbing alcohal
424531
Flip that bad boy over.   Print head facing up.\nYou see that little circle on the underside.   Well if you remove the circular tape it will reveal a small ball bearing.  \n\nBefore you complete the next step I strongly recommend that you have a kit designed for this cartridge.   Punch that little ball bearing inside the cartridge.  Voila a place to fill!\n\nThere is no sponge inside this cartridge rather air bags.  You are going to want to force a little air through this whole to separate the bags.  Inject 40 ml of ink. Seal up with new ball bearing (if you have the proper refill kit you will have them (standard B.B's sometimes work as well) \nthere should be no leakage around the sides of the ball bearing!  Finally cover the ball bearing hold with some electrical tape.\n\nIt's done.
199579
Consider the five basic machines, The lever and fulcrum, The inclined plain, The wheel and axle, The screw and the pulley.\n\nStart with a boyscout pine block racer kit, sand the wheels so that the tread is rounded rather than flat to reduce friction. for the undriven wheels put the nails in the wheels and deposit a liberal amount of petroleum based oil on the axle. This will cause the plastic to swell slightly for a good fit to the axles to prevent wobble, be sure to clean all the flash off of the nails first and polish them.\n\nThe driven wheels willneed a fixed axle that connects the wheels.
1038623
try here---\n         http://www.bearings.machinedesign.com/
761706
take plastic, turn in into a ball.... its not rocket science man!
761342
We did something like this in my physics lab with an Atwood machine.  It was a pully with weights hanging from it.  I can't exactly remember how it worked, but maybe this will inspire you.  We also did something with an air track and these two masses colliding and we'd see which one would go in which diretcion.  You need a nearly frictionless surface, like an air hockey table or ice slab.
748213
Try Edmund Scientific on the web..but if you want to make your own try the link provided.\n\nGood luck!