At University all engineering students shared a common first year. We all took 101 level:

  • Calculus
  • Physics
  • Communication
  • Chemistry
  • Computer Science and
  • A hands-on Laboratory class.

I always loved the lab because you would see the science at work in a real situation. I still remember it today that my favorite lab was one about fluid flow in pipes. You’d add some energy to the flow with a pump and measure the height the water could flow up to depending on how much energy you added to it. Fluid flow in pipes is quite simple, really. And this past weekend when I was out looking for a pressure washer it made me reminisce back to that lab because a pressure washer is just adding some energy to water to make it useful. For example, to clean surfaces – removing dirt and grime…

….So I wanted to write a post about my favorite 2 simple yet useful technologies for use around your home. They are: A pressure washer and a vacuum cleaner. I won’t go into too much detail about the engineering how each works but I just wanted to marvel at their wondrous simplicity and usefulness.

Pressure Cleaner

Of the 3 technologies in today’s post, I would guess the lowest percentage own a pressure washer. But I just bought one and let me tell you: they are amazing.

Here’s the deal:

You can get an electric pressure washer for about $150. An electric is what I bought. You plug it into your normal electric outlet and that powers a motor which powers a pump that adds enough energy to blast surface clean. All you do is plug it to the outlet for electricity and hook up your garden hose for water.

If you’re after more power you can get a gas power washer which is more expensive at around $400. With a gas unit you get more power, durability and noise. Because it has all the moving components of an internal combustion engine it will also require more maintenance.

The concept is so simple: Add energy to water to make it useful. I’m surprised it took me so long to start using one.

Vacuum Cleaner

I’m guessing you own a vacuum? But how often have you thought about how it works? Probably never. Well it works on the same principles as fluid flowing through a pipe, just like my favorite lab in first year University. Air is a fluid for all intensive purposes. And a vacuum cleaner uses an electric motor to turn a fan to pull air from the room through its intake port where the rotating brush is. As it pulls this air it pulls all the dirt from the carpet into its dust bag.

That’s it.

So with a pressure washer you push water through a hose and with a vacuum cleaner you pull air through a hose. Pretty amazing how simple it is when you break it down, hey? And a vacuum cleaner is considered a household essential – just like a fridge. Pretty cool.


It’s amazing how two seemingly different pieces of equipment work on the same principles of science. And funnily enough both are used to clean stuff.