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The Natural Philosopher[_2_] The Natural Philosopher[_2_] is offline
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Default The physics of cars - a question sequence.

On 30/03/16 19:53, bert wrote:
In article , Roger Mills
writes
On 30/03/2016 00:37, Dave Plowman (News) wrote:
In ,
Roger wrote:
This clearly shows you get more force by choosing peak power in a low
gear over peak torque in a higher one.


That's a no-brainer, anyway. Just as you can express engine power in
terms of engine speed (times) engine torque (divided by) a suitable
constant, you can also express propulsive power as road speed (times)
thrust at the contact patch (divided by) a different constant - but
they
should equate to the same thing apart from transmission losses. So when
the engine is developing its peak power, you'll get peak thrust at the
wheels.

Are you at it too? ;-)

Peak torque at the wheels happens when the engine is at peak torque -
not
peak BHP, unless the two coincide. Regardless of which gear you choose.


See my previous post. At any given road speed the max available thrust
at the wheels occurs when the engine is developing its max *power* not
its max *torque*. You choose the gearing to suit.

If you chose the correct gearing would the car achieve maximum seed at
maximum power output? In which instant the acceleration would be zero.


Peak power is always the place of maximum speed and maximum
acceleration, given suitable choices of gears



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