(Actually was thinking of something that rhymes with mass-hattery, but we’re family friendly here – SJS)
So – season’s first snow and coming midday like it did only portends ill…We were not disappointed.
So much road, so much snow — so many idiots.
But one in particular merited special attention as he went whizzing by, on the right, at a good 20 mph over the speed everyone else was keeping. So hey, bubba, guess you slept through the high school physics class, eh? A quick refresher to ponder whilst you wait.
In the ditch…
Newton’s First Law:
I. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.
This means that in the absence of a non-zero net force, the center of mass of a body either remains at rest, or moves at a constant speed in a straight line. Like, oh, perhaps a Mustang doing 70 in snow that encounters a patch of ice. On a curve.
Newton’s Second Law:
II. The relationship between an object’s mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors (as indicated by their symbols being displayed in slant bold font); in this law the direction of the force vector is the same as the direction of the acceleration vector.
This is the most powerful of Newton’s three Laws, because it allows quantitative calculations of dynamics: how do velocities change when forces are applied, i.e., according to Newton, a force causes only a change in velocity (an acceleration);
Newton’s Third Law:
III. For every action there is an equal and opposite reaction.
This law also carries a societal application as well. Sort of like the hand wave from that pick-up truck in front of me as it passed you, saluting your savvy wet/snowy/icy driving abilities, demonstrated so competently when you cut him off to jump into the lane. That is, before you demonstrated Doc Newton’s First Law.
Oh, and another useful item you may have slept/daydreamed through (or was presented on one of the days you just decided not to go to school): Friction. Let’s talk about friction. When you slide your book on the floor, it will come to stop because of the force of friction. Friction is the force that acts between two objects in contact because of action-reaction. Objects like, perhaps, tire(rubber) and road, eh?
Force of friction can be calculated by the formula
* Ff is the force of friction in N,
* μ the coefficient of friction, and
* FN is the normal force in N.
The value of μ depends on the surface you are dealing with. The following table shows some examples of μ.
|Surface||Value of μ|
|rubber on dry asphalt||~1|
|rubber on wet asphalt||0.95|
|rubber on ice||0.005|
For your edification, I sort of highlighted the relevant information for you. FYI – the more μ approaches 1 the better your stopping/roadholding.
To recap -
Speeding in snowy/icy road conditions: bad
Mustang in ditch: bad, very bad (especially since I am a Mustang kind of guy)
Bad driver, bad.
Doc Newton – undoubtedly laughing right about now (good).