Happy birthday, Takayasu!
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I want to like this one, but ‘break’ ruins it for me.
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I think it’d be more like:
lateral accelerator
(non-trivial) negative accelerator
positive accelerator
What if the car is in reverse?
Why would that matter?
speed is directionless . . . and that is what those bottom two pedals control.
Negative acceleration is not a thing. Acceleration is directional.
Perhaps increased friction control.
Been a while since I took physics, but isn’t deceleration another way of saying negative acceleration?
If I’m driving in a straight line at 50 mph and gradually slow to 20 mph, still traveling forward in the same straight line, I have experienced negative acceleration. Right?
Nope. You have experienced acceleration in the direction opposite to your current velocity or technically opposite to your inertial vector. Since velocity is point in time measure.
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Acceleration is the change in velocity over the change in time.
If my direction is constant and my velocity decreases then I’m going to have a negative in the numerator and a positive in the denominator.
Khan Academy seems to think that negative acceleration is a thing, as do numerous other sources.
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Of course!!
And exchanging money is also directional. Money going out is a debit . . . money coming in is a credit.
Profit is . . . directional to the degree that you can use strictly non-negative values but have to use additional terms to indicate the “net direction” . . .
Or assume that a “positive” value is one direction and “negative” value is the opposite direction.
Those pedals have an impact in opposite directions (in terms of impact on speed).
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The conflict here boils down to the underlying coordinate system.
If it’s a 1-D situation where the car can only move forward then it makes sense for the gas pedal to produce positive acceleration and the brake to provide negative acceleration.
If you define positive to match the direction of the velocity vector then it also works out. Gas=positive, brakes=negative. Even if the car is in reverse.
The steering provides acceleration perpendicular to the velocity, so only the direction changes (ideally - in real life friction provides some negative acceleration)
I kind of want to smack a bunch of you.
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Actually… often when I pull out, I start by going in reverse a bit, switch to drive, and hit the gas while my car is still rolling backwards.
but in lieu of that
here
have a TMBG video (and yes, Marty Beller is part of the band)
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Have another video from the same album
I just like it
it makes me smile
elephants are made of elements
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But yeah, I agree that negative numbers are complete bs.
I agree
all are vectors
Am I still at the top of that list?