Sundries

The 23rd edition of the Skeptics Circle is online if you’re interested.

Take a look at the straight dude’s guide to Brokeback Mountain.  It’s terribly funny.

A serious moment: Can you think of anything worse for a parent than both of your children dying in car accidents only minutes apart?  Kentucky sheriff’s deputy Andy McDowell recently lived this horror.

Ford caved to the radical Christian right’s American Family Association by endorsing our country’s blatant social war against homosexuals.  The AFA threatened a boycott of Ford if they did not curtail their advertising and support of gay publications and community activities.  While the specifics of Ford’s concessions remain unclear, there is no doubt that they have joined the bigoted battlefield of Christianity in an attempt to further subjugate gays and relegate them to second-class citizens.  If this keeps up, we will soon be sitting at the back of the bus.

I will respectfully disagree with Mark regarding this airplane on a conveyor belt riddle.  The riddle is this: if a plane is propelled forward with 100 knots of thrust while it is sitting on a conveyor belt moving backward at 100 knots, can the plane take off? While Mark accuses others of not being able to disengage their view of the plane as a car in this scenario, it is Mark who is unable to disengage not seeing the plane as a car in this scenario.  He says that “an airplane moves itself forward by moving air,” but this is entirely incorrect.  An airplane moves itself by moving through the air.  You see, while the plane is on the ground, it is bound by the very same physics laws that control how cars behave.  This is true because the plane’s motion on the ground is controlled entirely by its landing gear wheels, not its ability to fly or its wings or its engines.  Free-rolling wheels on a plane act in precisely the same manner on the ground as tires do for a car in gear.  The plane’s forward motion is accomplished when the engines create thrust, the thrust pushes the airframe forward, the airframe pushes the landing gear forward, and the landing gear wheels begin moving in relation to the ground.  If the ground’s movement is not relevant in this riddle, then runways and landing gear are both unnecessary as every plane can simply fly into the air from a stationary position by applying sufficient engine thrust.  You must realize the plane only flies because it can create forward motion while on the ground that in turn can create sufficient lift under the wings.  The riddle poses that the plane is on ground moving in the opposite direction the plane wishes to go, and it is moving at a speed equal to that of the plane.  Because the aircraft is pushed forward at the same velocity as the ground’s backward motion, it remains stationary as its speed is cancelled by the speed of the conveyor belt.  If the wheels cannot move forward, the plane is unable to push air around the wings to create lift.  Again, saying its position relative to the ground is not important is saying that a plane need only engage its engines with sufficient thrust in order to fly — no runway or landing gear needed.  To make his example scientifically accurate, you merely need push the Matchbox car forward at the same rate of speed that the paper underneath it moves backward.  The car remains stationary in relation to the ground because its forward momentum is absorbed by the paper’s backward momentum — where the rubber meets the road, so to speak.  This is where a plane gets its ability to take off: by acting like a car on the ground and building up sufficient speed so that the flow of air creates force under the wings that pushes the aircraft upward.  Despite his best intentions, Mark attempted to solve the riddle through aerodynamics.  Sadly, aerodynamics are irrelevant until the aircraft has forward momentum.  If the aircraft’s wheels are kept stationary in relation to the ground by moving the ground backward at the same rate the wheels move forward, there can be no forward momentum, no airflow, no lift, no aerodynamics, and therefore no flight.  Remember that a plane is “driven” while on the ground; it is not flown.  The answer to the riddle is that the plane will not be able to take off until its forward momentum as measured against whatever ground it rests on increases to sufficient velocity for creating lift.

Michael Viscardi is a great choice for ABCNews’ Person of the Week.  He’s 16 years old and has successfully updated a 19th century mathematical law which explains how heat travels across the surface of metal.  By clarifying the law and solving its unanswered questions, Michael’s theory “can be applied to all shapes and sizes of metal. The research could lead to better airplane wing design, better stabilization of the NASA space shuttle, and high-speed rail transportation.”  Oh, and he plays several musical instruments and knows that this is equally important to him as the math he so loves.  What a smart kid!

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