Frazz by Jef Mallett for October 30, 2011

He’s not going anywhere! Like standing on a sailboat and blowing the sails!

He got the idea, from Wile E. Coyote. The bag should say ACME on it.

MYTHBUSTERS SHOWED THAT THIS ACTUALLY WORKS

Okaaaaay…… I’ve never seen this, so my reacttion was the same as Rich Hobbes’.

If it does work, which direction does he go?

There’s no hole in the bottom of the bag for jet propulsion….

so does the air actually turn around and rush back out the top, then, and propel him in the direction of the bag?

Pretty counter-intuitive!

He’d go faster without the bag. If the bag pulls him won’t he be going backwards?

Without the bag, he would in principle be driven backward, but I don’t think the force would be great enough to overcome friction, because I have never even noticed reaction force when using a leaf blower.

With the bag, he could go forward if it is suitably shaped, because air is drawn in from all directions but the bag would primarily emit air backward. I would not have expected that configuration to be more effective, but maybe the difference is due to entrained air; it is sent backward at lower velocity but higher mass-rate. I am thinking about how the first jet engines emitted a narrow, concentrated blast, but modern jet engines are more efficient, because most of the air that they take in bypasses the combustion chamber and only adds to the mass flow rate.

Wheee. Almost wet my pants…

Another use for duct tape! lol

I think it would work, but I don’t think he’ll go very fast.

Me, I’m trying to figure out how it’s going to ruin his jeans. If the kid is just going to, er, brown the jeans, that wouldn’t be cause to throw them out. Maybe the blower leaks oil?

Ok, I’ll fess up, I don’t understand how it’s going to ruin his jeans either.

I suspect Frazz doubts he’ll be staying on the board very long.

He’s going to fall and rip up his pants.