National Free Flight Society

SEN 2743

  1. Newton 1, 2, 3, and 4
  2. Bike and more for sale

Newton 1

From:Tony Robertson

In answer to Gil Morris’s question, the answer is yes it takes energy to reverse the direction of the piston and connecting rod. If a body is moving in a straight line, an outside force is needed to change its direction and/or speed. The piston has to stop movement in the ‘down’ direction and then start movement in the ‘up’ direction. F = M*A

Tony Robertson


Newton 2

From:Mike Fantham

Under the misquote of Sir Isaac’s first law, the question of efficiency of a reciprocating piston F1C motor is raised.   Since there’s a swept volume limit, a non-reversing piston motor gets one stroke so the reciprocating piston is massively more efficient.


 

Newton 3

From aram schlosberg

Newton’s first law and efficiency
The first Newtonian law of motion applies to bodies moving linearly, rotating bodies or their combinations in a vacuum, without gravitational forces. The rotating part of an engine is the crankcase and prop. The whole model can move linearly.
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Under these conditions, the rotating speed of the crankcase and the prop as well as the direction the model is moving are preserved forever. The piston and connecting rod are redundant.
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But with air, friction and gravity the piston and connecting rod are required to convert repeated fuel combustion in a cylinder (via an up and down linear motion) into rotating the crankcase and prop – retaining the trust to keep the model in the air with enough lift to balance its weight.
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An engine’s efficiency is the way to achieve this with the least amount of fuel or given the amount of fuel, retain the highest rpm. In short, efficiency only matters in the real world. ///


 

Newton 4

From:Jerry Fitch

RE Newtonian Trivia:  The answer is no.  Efficiency is about energy.
Newton’s law  is about force.  Two different things, often confused.


Bike and more for sale

From:William   Shailor

FOR SALE
I am selling my 2000 Honda XR 100 that I bought new in 2000. It has only been used for chasing models at Lost Hills. It’s never been jumped, raced or laid down. It hasn’t been ridden in 6 years and is pretty dusty. Tires are flat, but should hold air. It had fuel preservative added when parked.  Included is my Lost Hills Storage spot in shed number one, along with a dining fly, folding chairs, a folding table, a bunch of tools (including everything needed to change an inner tube) as well as cable locks, hold down straps, etc. I’m asking $1,500.00. Email me at wmpjshailor@comcast.net.
Thanks,
Bill Shailor