How much power does it take? That's today's topic here at THE MAIN THING. Scientifically speaking, power is a measurement of how much energy is transferred per unit of time. Energy is often measured in joules, and 1 joule per second is a watt, named after James Watt, the inventor of the steam engine.

"A what?" my editor asks.

"Yes, that's correct. A watt." I reply.

"No, 'what.' I'm asking 'what.'" She is being patient with me.

"Why would you ask Watt? He's been dead almost 200 years."

"No! 'What' is the question I'm asking." She's annoyed, I can tell.

"How can I possibly give you a correct answer if you don't even know the question you're asking?"

My editor leaves the room muttering under her breath. Weird.

Heating 1 kilogram of water 1° Celsius uses 1 kilocalorie, or 4184 joules of energy. Confusingly, 1 kilocalorie is also 1 nutritional calorie. So for example, a bowl of chocolate ice cream contains 430 nutritional calories, or 1,799,120 joules of energy. That's a lot of nutrition! If I eat that bowl of chocolate ice cream in 3 minutes (trust me, I can do it), I'm transferring almost 10,000 watts. That's impressively powerful.

Especially in terms of horsepower, a unit of power equal to 550 foot-pounds per second, or 745.7 watts. During the 3-minute ice cream energy transfer described above, I'm doing the work of 13.4 horses. I begin to understand the origin of the expression "eating like a horse." That's really powerful.

In the movie Back to the Future, the time-traveling DeLorean requires 1.21 gigawatts of power when traveling at 88 miles per hour to overcome the constraints of normal space-time. That's a lot of power! That's like me and 121,000 of my closest buddies simultaneously eating bowls of chocolate ice cream in 3 minutes! Can you even imagine?

To overcome Earth's gravitational pull requires an escape velocity of 11.2 kilometers per second. That's really fast! It doesn't actually have anything to do with the power thing we're talking about today, but I think it's interesting, don't you?