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| Richard M |
 Posted: Fri Feb 04, 2005 8:28 pm |
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Could someone please tell me why a vehicle's speed can't increase by 10
ms^-1 instantaneously in the physical world. Suppose if it could, how
how would a speedometer read this? |
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| Guest |
| Posted: Fri Feb 04, 2005 8:28 pm |
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Richard M <richard.mcpherson@gmail.com> wrote:
[quote:e3a4c4b160]Could someone please tell me why a vehicle's speed can't increase by 10
ms^-1 instantaneously in the physical world. Suppose if it could, how
how would a speedometer read this?
[/quote:e3a4c4b160]
An instantaneous speed change means an infinite acceleration which
means an infinite force.
A speedometer can't change instantaneously either.
--
Jim Pennino
Remove -spam-sux to reply. |
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| Ornik Valid |
| Posted: Fri Feb 04, 2005 8:46 pm |
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"Richard M" <richard.mcpherson@gmail.com> wrote in message
news:1107566885.832947.28070@o13g2000cwo.googlegroups.com...
[quote:6fa394f68f]Could someone please tell me why a vehicle's speed can't increase by 10
ms^-1 instantaneously in the physical world. Suppose if it could, how
how would a speedometer read this?
[/quote:6fa394f68f]
Velocity change requires acceleration.
If by instantaneously you mean Zero, infinite acceleration is required
V = a*t, where you imply t = 0
If t = 0.0000001 sec then a is finite.
How much money do you have for the speedometer design phase? |
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| Sam Wormley |
| Posted: Fri Feb 04, 2005 9:00 pm |
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Richard M wrote:
[quote:bd13ccfe7a]Could someone please tell me why a vehicle's speed can't increase by 10
ms^-1 instantaneously in the physical world. Suppose if it could, how
how would a speedometer read this?
[/quote:bd13ccfe7a]
Acceleration
http://scienceworld.wolfram.com/physics/Acceleration.html |
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| PD |
| Posted: Fri Feb 04, 2005 9:52 pm |
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jimp@specsol-spam-sux.com wrote:
[quote:719b6913db]Richard M <richard.mcpherson@gmail.com> wrote:
Could someone please tell me why a vehicle's speed can't increase
by 10
ms^-1 instantaneously in the physical world. Suppose if it could,
how
how would a speedometer read this?
An instantaneous speed change means an infinite acceleration which
means an infinite force.
A speedometer can't change instantaneously either.
--
Jim Pennino
Remove -spam-sux to reply.
[/quote:719b6913db]
Gee, I dunno. Rode on a Harley one time that came damn close. I bet
with nitro it could.
PD |
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| CWatters |
| Posted: Sat Feb 05, 2005 5:49 am |
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"Richard M" <richard.mcpherson@gmail.com> wrote in message
news:1107566885.832947.28070@o13g2000cwo.googlegroups.com...
[quote:6d28111e02]Could someone please tell me why a vehicle's speed can't increase by 10
ms^-1 instantaneously in the physical world.
[/quote:6d28111e02]
F=MA
when A = very large, F is very large.
[quote:6d28111e02]Suppose if it could, how how would a speedometer read this?
[/quote:6d28111e02]
As a step change in speed.. however since the spedo pointer has mass it also
can't move from one position to another instantly. A similar problem will
occur with electronic speed sensors. |
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| Uncle Al |
| Posted: Sat Feb 05, 2005 11:47 am |
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Richard M wrote:
[quote:223c8caee1]
Could someone please tell me why a vehicle's speed can't increase by 10
ms^-1 instantaneously in the physical world. Suppose if it could, how
how would a speedometer read this?
[/quote:223c8caee1]
How is "impulse" calculated? Plug in the numbers. Wht is the slope
of a delta function? Of any instantaneous change?
--
Uncle Al
http://www.mazepath.com/uncleal/
(Toxic URL! Unsafe for children and most mammals)
http://www.mazepath.com/uncleal/qz.pdf |
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| PD |
| Posted: Sat Feb 05, 2005 12:18 pm |
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Richard M wrote:
[quote:543ddb0e2f]Could someone please tell me why a vehicle's speed can't increase by
10
ms^-1 instantaneously in the physical world. Suppose if it could,
how
how would a speedometer read this?
[/quote:543ddb0e2f]
Let me turn this into a more parochial question back at you.
You are proud of your car, with its fuzzy dice hanging from the mirror,
a Hurst tachometer, a GPS system, and the other usual instrumentation.
What in your car measures the following:
Distance traveled?
Displacement?
Speed?
Velocity?
Acceleration?
PD |
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