- Tony Sandy
- United Kingdom
Is there an advantage of spin over percussion, when it comes to moving objects through space?
I've noticed that frisbees*, drills, javelins, propellers (planes, submarines, helicopters), arrows, rifling in gun barrels all cause spin or spin naturally. Is this because forward momentum creates displacement (pressure at the front/ vacuum at the back or in the case of deliberate propulsion as in jet engines, vacuum at the front, forward momentum from the back as the sucked in air expands at the back, pushing the craft forward)?
Also does percussion as in hammer drills and the rocket that was supposed to be propelled by minor nuclear explosions (staccato versus smooth flow), have any advantage over spin (think also of nail versus screw or saw versus axe)?
*discs show lack of resistance all round, by transferring what part of the edge is facing forward as pointed objects keep the narrowest part of themselves in the forward position - likewise spheres spin in the same way as discs, being rotated by friction, I believe.