Remember your HS Physics?

DrewE wrote:

GordonThree wrote:
KE unit is joules right? I'm fuzzy on that part of highschool physics too, just how much is a joule ... is it the amount of energy that'll raise one g of water one degree c or something like that?

That would be a calorie (with a small c), one thousandth of a Calorie (with a big C) or kilocalorie that is used for foods. A joule is a kilogram meter squared per second squared (which clears everything up, right?), or equivalently a watt-second. It's a bit less than a quarter of a calorie (with a small c).

Naturally, the nature of the relationship between kinetic energy and velocity is the same regardless of what units one uses. In terms of surviving a crash, arguably more important than the total energy dissipated is the rate of deceleration, which incidentally has a lot to do with how large crush structures on vehicles need to be in order to be effective.

Yep, he got it right.

If the velocity is in meters/sec and the mass is in kilograms, the energy is in joules. A joule is not very much energy, but when you start talking about 10,000 kg traveling at 60 mph (26 m/sec), it turns into a lot of energy.

So..... slow down.

Let's boil it down to simple terms for non-technoweenies like me:

Sure, you can tow it, but can ya STOP it????

aerbus32 wrote:
The question often comes up on RV forums about how fast people drive their rigs and disagreements ensue. Just saying . . . Do the math.

Wouldn't f = ma be more appropriate?

GordonThree wrote:
KE unit is joules right? I'm fuzzy on that part of highschool physics too, just how much is a joule ... is it the amount of energy that'll raise one g of water one degree c or something like that?

That would be a calorie (with a small c), one thousandth of a Calorie (with a big C) or kilocalorie that is used for foods. A joule is a kilogram meter squared per second squared (which clears everything up, right?), or equivalently a watt-second. It's a bit less than a quarter of a calorie (with a small c).

Naturally, the nature of the relationship between kinetic energy and velocity is the same regardless of what units one uses. In terms of surviving a crash, arguably more important than the total energy dissipated is the rate of deceleration, which incidentally has a lot to do with how large crush structures on vehicles need to be in order to be effective.

Isn't kinetic energy the result of a Prevost coach and a Toyota Prius connecting in an intersection when both drivers thought they had the right of way?

I don't remember high school physics because I never had it. I was in bonehead math.

But even in bonehead math I learned:

The faster you go, the more its going to hurt when you hit something.

KE unit is joules right? I'm fuzzy on that part of highschool physics too, just how much is a joule ... is it the amount of energy that'll raise one g of water one degree c or something like that?

Well, I had an uncle that always said, "drive fast, love hard, die young, and leave a beautiful memory!"