Jennifer R. Vail

There's different things that can cause it.

And there's also friction when you first start sliding.

to move versus the friction during movement.

And again, if we go back to moving a box, you know, when you first try to push it, you have to really give it an oomph.

That's because the friction at that startup is higher than the friction once you get things moving.

So lots of different types of friction and different things we have to do to study and understand and manipulate them.

Yeah, friction better be in that formula.

Otherwise, things will start to go very wrong.

So friction is part of the basic mechanics and physics of the world around us.

So one of my favorite examples of this, if you've ever been to a theme park or amusement park, you know, there's a style of ride where the passenger vehicles are all just connected to each other.

in a continuous chain.

And in one case that I'm at least aware of, I'm sure this has happened many times, they went to turn on a brand new ride designed in this style, and the thing didn't move.

And the reason it didn't move is because they didn't take account

That startup friction being as high as it would be.

It wasn't really well understood in that design.

And they had to add more power into pushing everything to turn it on to overcome the friction.

So if you neglect friction or you don't understand it properly, it will make you pay.

And in that case, literally stalled them out.

Yeah, it's actually really remarkable.

I think that all the time I live near a railroad track and we get really long trains and I just think all the time how much power you have to get just to get the thing moving.