In what direction will the bike move?

valamhic

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There is a perfectly flat tarmac surface on a street and it is a calm sunny warm day. Jack has just got his first bicycle and is learning to ride it. It is a large child's bike
with stabilizers on the back wheels to keep it upright. The front wheel is aligned with the back both facing in he same direction and Jack puts a lock on the handle bars
which prevents it turning and being stolen. The 2 wheels are free to revolve freely. It has just one gear, a big cog wheel on the pedals and a small free wheel on the back wheel connected by a normal chain. which allows Jack to coast forward down hill without the pedals going round. Its a plain standard traditional bike in every way.

The right pedal is down near the bottom at 5 o'clock and a man standing there talking to his neighbour has no evil intent. This man puts his foot against the right pedal and pushes it backwards. The pressure is enough to move the bike itself, The man is not in contact with the bike at all.

Question: Does the bike move forward or backwards?
 

Ire-land

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If it’s in gear, which presumably it is as it’s only got one, and the pedal is at 5 o’clock, then there’d be enough in gear rotation to move the bike forward.
 

BSA

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Unless you provide full details we cannot answer this question...

  1. What colour is the bike?
  2. Has it a bell ?
And the most important thing... is it a ladies or gents bike?
Once these facts are known the answer is obvious..
 

Ted

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And..
When the bike moves, what part of it doesn't move?
 

valamhic

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If it’s in gear, which presumably it is as it’s only got one, and the pedal is at 5 o’clock, then there’d be enough in gear rotation to move the bike forward.
There are no gears on the bike, just a chain drive round the two cog wheels. Just a single speed,
 
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A similar question can be applied to pulling on a spool of thread, which direction will the spool go if you pull the thread.
 
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Wolf

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There is a perfectly flat tarmac surface on a street and it is a calm sunny warm day. Jack has just got his first bicycle and is learning to ride it. It is a large child's bike
with stabilizers on the back wheels to keep it upright. The front wheel is aligned with the back both facing in he same direction and Jack puts a lock on the handle bars
which prevents it turning and being stolen. The 2 wheels are free to revolve freely. It has just one gear, a big cog wheel on the pedals and a small free wheel on the back wheel connected by a normal chain. which allows Jack to coast forward down hill without the pedals going round. Its a plain standard traditional bike in every way.

The right pedal is down near the bottom at 5 o'clock and a man standing there talking to his neighbour has no evil intent. This man puts his foot against the right pedal and pushes it backwards. The pressure is enough to move the bike itself, The man is not in contact with the bike at all.

Question: Does the bike move forward or backwards?
Tuesday.
 
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Ire-land

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There are no gears on the bike, just a chain drive round the two cog wheels. Just a single speed,
That's in its one gear, I was just breaking it down for clarity.

And it would actually go backwards- I just testing my bike! I'm surprised by that tbh.
 

valamhic

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OK, thanks for all the genuine replies.

It will go backwards. It will move opposite to the force being applied.
 
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