Why a bike can balane when the wheelse

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Discussion Overview

The discussion centers around the stability of a bicycle when stationary versus when in motion, exploring concepts of equilibrium and angular momentum. Participants examine the conditions under which a bicycle can balance and the implications of wheel rotation on stability.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants note that a bicycle can balance when stationary but is in an unstable equilibrium, requiring precise positioning to avoid falling.
  • Others explain that when the wheels rotate, the bicycle achieves stable equilibrium, with references to changes in the energy diagram.
  • One participant describes the effect of leaning while riding, suggesting that tilting a rotating wheel causes it to turn in a way that helps maintain balance through angular momentum conservation.
  • A participant questions the initial post, pointing out a potential redundancy in asking and answering the same question.
  • Another participant expresses uncertainty about how the concepts of stable and unstable equilibrium apply specifically to bicycles.

Areas of Agreement / Disagreement

Participants express differing views on the nature of balance in bicycles, with some agreeing on the concepts of stable and unstable equilibrium while others seek clarification on how these concepts manifest in the context of bicycle dynamics. The discussion remains unresolved regarding the specifics of these dynamics.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about equilibrium states and the definitions of stability as they apply to bicycles. Some mathematical or physical steps in the reasoning are not fully explored.

nzahra_ghasemi
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why a bike can balane when the wheelse don't rotate but it is unstable
and when the wheeles rotate it will be stable equilibrum
it means that the maximum of E-x diagram change to it's minimum
 
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nzahra_ghasemi said:
why a bike can balane when the wheelse don't rotate but it is unstable
and when the wheeles rotate it will be stable equilibrum
it means that the maximum of E-x diagram change to it's minimum

Did you just asked a question and then immediately answered it yourself?

Zz.
 
A bicycle can "balance" when it is not moving in the same sense that you can balance a broom stick on your nose! IF you get it exactly right and then don't move you are fine- but even the slightest twitch will cause it to fall: unstable equilibrium.

As for a moving bicycle, the simplest way to think about it is this: If you tilt a rotating wheel, it will tend to turn in order to conserve angular momentum. Riding a bicycle, if you lean to the right, the front wheel will automatically turn to the right, "catching" you as you ride forward.
 
ZapperZ said:
Did you just asked a question and then immediately answered it yourself?

Zz.
i know the stable equilibrium is the min and the unstable equilibrium is the max of the diagram but i don't know how this happens in a bike
 
can you explain about "Euclid alone has looked on beauty bare" please
 
nzahra_ghasemi said:
can you explain about "Euclid alone has looked on beauty bare" please

I thought I'd already responded to this but it didn't "take" apparently!

If you are referring to the poem, it is a sonnet by Edna St. Vincent Millay:

Euclid alone has looked on Beauty bare.
Let all who prate of Beauty hold their peace,
And lay them prone upon the Earth and cease
To ponder on themselves, the while they stare
At nothing, intricately drawn nowhere
In shapes of shifting lineage; let geese
Gabble and hiss, but heroes seek release
From dusty bondage into luminous air.
O blinding hour, O holy, terrible day,
When first the shaft into his vision shone
Of light anatomized! Euclid alone
Has looked on Beauty bare. Fortunate they
Who, though once only and then but far away,
Have heard her massive sandal set on stone.
 

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