[Home]  [Headlines]  [Latest Articles]  [Latest Comments]  [Post]  [Sign-in]  [Mail]  [Setup]  [Help] 

Status: Not Logged In; Sign In

UK economy on brink of collapse (Needs IMF Bailout) How Red Light Unlocks Your Body’s Hidden Fat-Burning Switch The Mar-a-Lago Accord Confirmed: Miran Brings Trump's Reset To The Fed ($8,000 Gold) This taboo sex act could save your relationship, expert insists: ‘Catalyst for conversations’ LA Police Bust Burglary Crew Suspected In 92 Residential Heists Top 10 Jobs AI is Going to Wipe Out It’s REALLY Happening! The Australian Continent Is Drifting Towards Asia Broken Germany Discovers BRUTAL Reality Nuclear War, Trump's New $500 dollar note: Armstrong says gold is going much higher Scientists unlock 30-year mystery: Rare micronutrient holds key to brain health and cancer defense City of Fort Wayne proposing changes to food, alcohol requirements for Riverfront Liquor Licenses Cash Jordan: Migrant MOB BLOCKS Whitehouse… Demands ‘11 Million Illegals’ Stay Not much going on that I can find today In Britain, they are secretly preparing for mass deaths These Are The Best And Worst Countries For Work (US Last Place)-Life Balance These Are The World's Most Powerful Cars Doctor: Trump has 6 to 8 Months TO LIVE?! Whatever Happened to Robert E. Lee's 7 Children Is the Wailing Wall Actually a Roman Fort? Israelis Persecute Americans Israelis SHOCKED The World Hates Them Ghost Dancers and Democracy: Tucker Carlson Amalek (Enemies of Israel) 100,000 Views on Bitchute ICE agents pull screaming illegal immigrant influencer from car after resisting arrest Aaron Lewis on Being Blacklisted & Why Record Labels Promote Terrible Music Connecticut Democratic Party Holds Presser To Cry About Libs of TikTok Trump wants concealed carry in DC. Chinese 108m Steel Bridge Collapses in 3s, 16 Workers Fall 130m into Yellow River COVID-19 mRNA-Induced TURBO CANCERS. Think Tank Urges Dems To Drop These 45 Terms That Turn Off Normies

Science/Tech
See other Science/Tech Articles

Title: Brainteaser: There's an airplane on the runway..
Source: Elsewhere
URL Source: http://www.someplaceelse.com
Published: Dec 1, 2005
Author: I have no idea
Post Date: 2005-12-01 01:10:02 by Jhoffa_
Keywords: Brainteaser:, airplane, runway..
Views: 3058
Comments: 202

Imagine a plane is sat on the beginning of a massive conveyor belt/travelator type arrangement, as wide and as long as a runway, and intends to take off. The conveyer belt is designed to exactly match the speed of the wheels at any given time, moving in the opposite direction of rotation. There is no wind.

Can the plane take off?

Post Comment   Private Reply   Ignore Thread  

Begin Trace Mode for Comment # 99.

#61. To: Jhoffa_ (#0)

In my opinion, the plane will move forward and can take off. If I'm wrong I'm going to have to think twice about the worth of a physics degree, lol. Here's my reasoning.

There is a force applied by the thrust of the engines to propel the plane forward. Where is the opposite force to counter it and hold the plane motionless? There is only one possible source in this brainteaser: the wheels, or more specifically the axles the wheels are mounted on. How are the "as frictionless as we can engineer them" axles going to stop the plane from moving forward if they are allowed to freely spin? Yes, there is friction between the wheels and the ground, but where's the friction in the axles? Without that it does not matter what the wheels are doing. Without friction in the axles none of the "conveyer counter force" can be transferred to the plane.

One more attempt to explain the importance of the axle. When you apply brakes in your car, in an attempt to stop, you are forcing the axle to stop spinning. Unfortunately, your wheels also get a vote. On ice, they often choose to disagree. However, if you don't apply the brakes, at least as far as going forwards is concerned, your car is on a near frictionless surface no matter what surface you are on: pavement, ice, or conveyer belts. If the axle is allowed to freely spin you can pretty much rule out the wheels.

And lastly, why the conveyer belt? Just find a plane that can take off with the brakes fully applied (leaving long black skid marks until it gets airborne). Put a coyote in the cockpit, put a roadrunner at the end of the runway, and make sure the manufacturer of the engine is Acme! Beep! Beep! Hehehe :)

markm0722  posted on  2005-12-01   21:24:23 ET  Reply   Untrace   Trace   Private Reply  

There is a force applied by the thrust of the engines to propel the plane forward. Where is the opposite force to counter it and hold the plane motionless?

I like it. You can't argue with it or...

I've been keeping score and some of you folks are sad, real sad.

Just goes to show you how forums are not a good place to persuade. No matter how much explanation, logic, patience and repetition of same, folks stick to their guns. Did anyone here change their mind? No progress was made. Yet, there is a correct answer to the question. The plane does fly. No doubt, absolutely a fact. It will fly. It's not a matter of opinion. It's a fact.

Lesson to be learned: You may have the right to your opinion but, isn't it more important that your opinion be right? Isn't truth more important than ego? Isn't right more important than wrong?

Now, let's go one more round and work towards a consensus.

Their coming to take me away, ha ha

wakeup  posted on  2005-12-02   2:47:28 ET  Reply   Untrace   Trace   Private Reply  

Now, let's go one more round and work towards a consensus.

Well, we could hang a "Mission Accomplished" banner from the control tower.

I'm not helping our case, am I? Sorry about that. ;)

markm0722  posted on  2005-12-02   3:25:14 ET  Reply   Untrace   Trace   Private Reply  

#100. To: markm0722 (#99)

Clever.

Mission Accomplished fits, though.

It's a lie that will send most to another issue.

wakeup  posted on  2005-12-02 03:37:15 ET  Reply   Untrace   Trace   Private Reply  

Top • Page Up • Full Thread • Page Down • Bottom/Latest

[Home]  [Headlines]  [Latest Articles]  [Latest Comments]  [Post]  [Sign-in]  [Mail]  [Setup]  [Help]