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A reason I place stories in colder climates:
I walked through snow that reached past my boots (about half-way up my calves) in a snowstorm to pick up my kid and we consider this perfectly normal. It's not a reason not to get to school or work either; it's slightly poor weather.
I walked through snow that reached past my boots (about half-way up my calves) in a snowstorm to pick up my kid and we consider this perfectly normal. It's not a reason not to get to school or work either; it's slightly poor weather.
Related to this, here are some physics facts regarding driving safely in cold temperatures:
Pressure on ice forces the ice to take less space, meaning it melts — this is the same principle how gas under high pressure stays in liquid form in containers. 1/
Pressure on ice forces the ice to take less space, meaning it melts — this is the same principle how gas under high pressure stays in liquid form in containers. 1/
Ice and water is a bit special like that because of how ice has a lower density than water. I could go into this, but it's besides the point.
Anyway, this isn't really noticeable to the naked eye or anything, but that means a car can create a thin layer of water on ice. 2/
Anyway, this isn't really noticeable to the naked eye or anything, but that means a car can create a thin layer of water on ice. 2/
Ice by itself has friction, but combined with water, you can just as well ignore that fact — you will slide. This of course matters on how the water turned solid, but a flat surface with a thin layer of water is SLIPPERY. 3/
Now, breaking relies on friction. Without friction, you can't stop. Ice being slippery means there's a lack of friction and the two surfaces can slide against each other. Thus a sudden break when driving doesn't work well. Slowing down to use breaks is essential. 4/
Now, a way to solve the problem with icy roads is salt. The freezing point of a solution of water and salt lowers is about -17°C (1.4°F), and in climates where temperatures essentially never reach that low, this works fine. 5/
However, salt will stick to the wheels of a car, whether or not there's ice on it. This is not a problem if you drive on a normal road.
It can be life threatening, though.
Remember my mention about pressure and freezing points? 6/
It can be life threatening, though.
Remember my mention about pressure and freezing points? 6/
Well, if you driver onto a road with ice, physics happens. Pressure on ice turns liquid, salt lowers the freezing point, and the driver — presumably thing they're good — don't take precautions.
The car slides because of lack of friction, and an accident is bound to happen. 7/
The car slides because of lack of friction, and an accident is bound to happen. 7/
If temperatures are prone to hang around the freezing point of a salt solution, you rather not use that as a way to deal with it either, because physics makes it dangerous. 8/
All of this can apply to snowy roads as well, depending on several factors, so it doesn't make it safe.
So when on icy (and snowy) roads, always assume there will be little friction and that your car might slide like an ice cube on a clean kitchen counter. 9/9
So when on icy (and snowy) roads, always assume there will be little friction and that your car might slide like an ice cube on a clean kitchen counter. 9/9
Thanks for coming to my TED talk on safe driving.
[Note: I may have made some mistakes in the physics, but the general concept should be correct.
What I wrote about safe driving is all true, and I know it from sitting in the passenger's seat fearing death.]
[Note: I may have made some mistakes in the physics, but the general concept should be correct.
What I wrote about safe driving is all true, and I know it from sitting in the passenger's seat fearing death.]
