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Invisible wrote:
>>> Hmm, interesting. I wouldn't have expected that to work.
>>
>> What, that a car has more weight on the front wheels than the back?
>
> Possibly, once you've got the back wheels up on a ramp. ;-)
>
> I meant more that I wouldn't have expected to be able to just completely
> disregard 3/4 the weight of the object just because I'm only looking at
> one wheel.
>
The suspension of the car does play a part here. They are designed to
keep all four wheels on the ground, and as flat as possible, when going
through a corner. If the weight of the car started shifting around every
time you moved the center of mass on the interior or went into a banked
corner just a bit too fast, the car would not be very stable at all.
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"Invisible" <voi### [at] dev null> wrote in message
news:4b717a62@news.povray.org...
> Not obese, no. Also not fit. My arms contain very little muscle, and
> attempting to lift 100 Kg using only my arms operating in an unusual
Then don't lift your body; push the earth down.
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>> Not obese, no. Also not fit. My arms contain very little muscle, and
>> attempting to lift 100 Kg using only my arms operating in an unusual
>
> Then don't lift your body; push the earth down.
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Invisible wrote:
> Vincent Le Chevalier wrote:
>
>> What about all those doors you've pushed?
>
> A door isn't nearly as heavy as a person.
>
Some of the ones we had offshore weighed half a ton.
--
Best Regards,
Stephen
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>> A door isn't nearly as heavy as a person.
>
> Some of the ones we had offshore weighed half a ton.
Short or long?
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> Mass rises as the cube of size, but muscle power rises as the square of
> size.
I would have thought the strength of a muscle depends on its volume, why do
you say is rises with the square of size?
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scott wrote:
>> Mass rises as the cube of size, but muscle power rises as the square
>> of size.
>
> I would have thought the strength of a muscle depends on its volume, why
> do you say is rises with the square of size?
Muscle power is [apparently] proportional to cross-section area, not volume.
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>>> Mass rises as the cube of size, but muscle power rises as the square of
>>> size.
>>
>> I would have thought the strength of a muscle depends on its volume, why
>> do you say is rises with the square of size?
>
> Muscle power is [apparently] proportional to cross-section area, not
> volume.
I guess that makes sense if you assume each cell in the muscle fibre can
only exert a certain force, a chain of them can still only exert that same
force no matter how long it is. It's having more fibres in parallel that
help to increase the force.
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>> Muscle power is [apparently] proportional to cross-section area, not
>> volume.
>
> I guess that makes sense if you assume each cell in the muscle fibre can
> only exert a certain force, a chain of them can still only exert that
> same force no matter how long it is. It's having more fibres in
> parallel that help to increase the force.
Precisely.
Also of note is that [apparently] if all the fibers were to contract
simultaneously, the muscle would be ripped from the bone (assuming
there's any load on it). Apparently the fibers are actually programmed
to twitch a few at a time, so that they have time to recover between
contractions, while the muscle as a whole maintains constant force.
You know how when you try to lift something too heavy and you start
shaking? That's apparently because there aren't enough fibers fiting at
once...
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Invisible a écrit :
>>> Not obese, no. Also not fit. My arms contain very little muscle, and
>>> attempting to lift 100 Kg using only my arms operating in an unusual
>>
>> Then don't lift your body; push the earth down.
>
> Mass of the Earth = 5.9742 × 10^24 Kg o_O
That's nothing, but the guys at the antipods are giving you some trouble
(as they push down too... to your side!)
--
A: Because it messes up the order in which people normally read text.<br/>
Q: Why is it such a bad thing?<br/>
A: Top-posting.<br/>
Q: What is the most annoying thing on usenet and in e-mail?
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