Non-motoring > Puzzle trivia thread	Miscellaneous
Thread Author: Runfer D'Hills	Replies: 21

New Sun 4 Apr 10 12:23   Puzzle trivia thread - Runfer D'Hills

OK - I'll start. Assume you can throw a tennis ball at 50 mph You are on an airliner travelling at 500 mph You throw the ball from the back of the cabin to the front. Was the ball doing 550 mph ? If so, when you throw it back down the cabin was it actually doing 450 mph forwards ? If the stewardess caught it mid flight on the way back, did it stop or did it accelerate instantly to 500 mph ? I'm off for a bike ride now. See you later...... :-) Reply to this message | Report message

New Sun 4 Apr 10 12:43   Puzzle trivia thread - crocks

Was the ball doing 550 mph ? Yes, relative to the ground. ...was it actually doing 450 mph forwards ? Yes, relative to the ground. ...did it stop or did it accelerate instantly to 500 mph ? It didn't stop, relative to the ground. It accelerated to 500mph, relative to the ground, over a very short time. Last edited by: crocks on Sun 4 Apr 10 at 12:44 Reply to this message | Report message

New Sun 4 Apr 10 13:01   Puzzle trivia thread - -

As Crocks relative to the ground then as you described. From the inside of the plane it has only travelled back and forth at 50mph, and probably caused someone's G & T to be spilled..criminal negligence. Reply to this message | Report message

New Sun 4 Apr 10 13:49   Puzzle trivia thread - rtj70

When holding the ball before throwing it, it was already doing 500mph relative to the ground. As it would be when caught. You'll be asking about flies hovering in a train carriage next ;-) Reply to this message | Report message

New Sun 4 Apr 10 13:52   Puzzle trivia thread - crocks

As a motoring forum surely this should all be on a coach at 60mph on the M1. Reply to this message | Report message

New Sun 4 Apr 10 14:50   Puzzle trivia thread - Zero

No the coach is a national express one, someone has removed the limiter and its doing 85 MPH. Reply to this message | Report message

New Sun 4 Apr 10 14:12   Puzzle trivia thread - Iffy

...bike ride... Swimming yesterday, bit of an eager beaver, aren't we Humph? I feel tired just thinking about it. Reply to this message | Report message

New Sun 4 Apr 10 15:12   Puzzle trivia thread - bathtub tom

A fly going north at 10MPH hits a car going south at 70MPH. The fly's speed must go from +10MPH to -70MPH. At the point the fly's speed is 0MPH does the car stop also? Reply to this message | Report message

New Sun 4 Apr 10 16:26   Puzzle trivia thread - Robin O'Reliant

No. At the point the fly is doing 0mph in a forward direction it's body mass is spreading sideways and compressing, thus not effecting the forward motion of the car. Reply to this message | Report message

New Sun 4 Apr 10 16:34   Puzzle trivia thread - Runfer D'Hills

Hmmm, all very fine and logical. Now, what effect on ground speed does the direction of travel of the aircraft in relation to the turning of the Earth on its axis have ? If for example the aeroplane was flying due east at the time of the ball being thrown what speed would it actually have achieved relative to the ground eh ? Reply to this message | Report message

New Sun 4 Apr 10 16:37   Puzzle trivia thread - Robin O'Reliant

Hmmm.... Depending on the speed surface of the Earth rotates, it might even be going backwards. Reply to this message | Report message

New Sun 4 Apr 10 16:59   Puzzle trivia thread - CGNorwich

About 1000 mph at the equator Reply to this message | Report message

New Sun 4 Apr 10 17:01   Puzzle trivia thread - Robin O'Reliant

>> About 1000 mph at the equator >> That's interesting. So how does a plane flying at 500mph actually get anywhere, or does it wait for it's destination to catch up with it? Reply to this message | Report message

New Sun 4 Apr 10 17:11   Puzzle trivia thread - Zero

No planes fly exactly round the equator. If you lived on the equator, and you wanted to fly to a place on the equator on the other side of the world, you could fly round in circles and wait for it to catch up, or fly the other way and get there twice as fast. or you could fly over the pole (either) but it would have moved by the time you got there and you would end up at home again. Never live on the equator - you can check out any time you like but you can never leave, Reply to this message | Report message

New Sun 4 Apr 10 17:18   Puzzle trivia thread - Crankcase

It gets interesting when you decide the plane is travelling at the speed of light, and someone turns on the headlights. Would they project a beam? Reply to this message | Report message

New Sun 4 Apr 10 17:24   Puzzle trivia thread - Runfer D'Hills

.....and in your plane Crankcase, would the ball thrown from the back of the cabin to the front have exceeded the speed of light ? Going for another swim now. Bike ride has made me stiff. Reply to this message | Report message

New Sun 4 Apr 10 17:29   Puzzle trivia thread - Robin O'Reliant

And if the plane was travelling at the speed of light x2, would the light beam shine backwards? Reply to this message | Report message

New Sun 4 Apr 10 18:37   Puzzle trivia thread - Fursty Ferret

>> It gets interesting when you decide the plane is travelling at the speed of light >> and someone turns on the headlights. Would they project a beam? >> Yes. As far as the plane is concerned, it is stationary and everything is moving with the speed of light in relation to it. Reply to this message | Report message

New Sun 4 Apr 10 18:43   Puzzle trivia thread - crocks

My Uncle Albert had a theory about this, but I can't remember what it was. Reply to this message | Report message

New Sun 4 Apr 10 20:15   Puzzle trivia thread - CGNorwich

There was a young lady named Bright, whose speed was much faster than light. She set off one day in a relative way, and returned on the previous night. Reply to this message | Report message

New Mon 5 Apr 10 06:08   Puzzle trivia thread - Pat

Why do wheels that are obviously going forwards appear to stop and start going backwards? Is it because my eyes and my brain can't go any faster? Pat Reply to this message | Report message

New Mon 5 Apr 10 10:49   Puzzle trivia thread - Zero

Its the stroboscopic effect. The film or tv you see has a refresh rate (flicker) when the refresh rate comes close to the revolutions of the wheel the effect is to make it seem to stop or revolve slowly in either direction. Last edited by: Zero on Mon 5 Apr 10 at 10:50 Reply to this message | Report message