This spring, I decided to learn to unicycle. And not just riding on smooth streets to say that I can unicycle, but riding the local mountain bike trails on one wheel. After about two and a half months of practice, I was good enough that it was worth driving to a park with good trails for a ride. I’d constantly ‘trip’ over roots, but there were enough smooth sections for it to be fun. I went back a few times, and each time I’d make it past some section that I missed the previous ride. Then something strange happened: one day I just couldn’t ride any more. I had unplanned dismounts (UPDs) in places I could fairly consistently clear an previous rides. In addition to the normal UPDs, I had a couple crashes, the last of which twisted my ankle enough that I had to take it easy for a couple weeks to give it a chance to recover. After that day, I couldn’t really ride for a month. Not that I didn’t try. I’d ride down a smooth street, and randomly fall off my unicycle. This continued for the entire month of August. Then September began, and I decided I was starting to recover my unicycling abilities enough that it was worth a trip back to the park with mountain bike trails. For the first twenty minutes, I could barely ride. Then all of a sudden, I could ride again. I began clearing sections I hadn’t made before. I even rode good parts of the intermediate trails instead of sticking to the beginner trail. Today I went back again and was able to ride even more sections that had previously caused me to UPD, and some I hadn’t even tried before.

The second example is solving physics and math problems. Some days, I’ll look at a new problem for a couple hours without any real progress. On other days, I could look at the same problem and solve it nearly as quickly as I can write the answer. This is particularly frustrating when I know I’ve solved similar problems easily in the past, but just don’t see the solution that day.

Static friction is greater than kinetic friction.^*

In other words, if you aren’t sliding, it is easy to stay not sliding. Once you start sliding, it is hard to stop.

So stop stomping on the pedals when you drive. You’ll just make your wheels spin or lock and slide. When you spin your wheels, you are just turning the snow into an ice slick, making it harder for you and everyone after you to start or stop. So please go easy on the pedal mashing.

Suggested reading:

• Friction on Eric Weisstein’s World of Physics
• Car Talk’s Official Click and Clack Winter Driving Rules

^*Except for some cases you probably won’t encounter.