### Sunday Science Quiz

Sunday, February 26, 2006
(Florida Today) CAPE CANAVERAL - A spacewalking Russian cosmonaut plans to hit a golf shot outside the International Space Station this summer as part of a publicity campaign that already has raised safety concerns.

Clad in a cumbersome spacesuit and anchored to a specially designed tee box, Pavel Vinogradov will hit a six-iron drive along side the station's Russian segment, taking great care not to hook the ball into the outpost.

Quiz question: why is it unlikely the ball would hook into the station?

terrye said...

Does it have something to do with that whole lack of gravity thing?

Is it true that things can not explode into a fireball in space because there is no oxygen?

chuck said...

Who cares, the on board laser cannon will vaporize it anyway.

Terrye,

Lack of air. A spinning object moving in air curves curves because the side moving against the air feels more pressure than the side moving with the air, a tennis ball with underspin rises, for instance. Tennis balls are fuzzy and golf balls are dimpled and I think this helps increase the effect. The details of what goes on can get pretty complicated.

Because hooks, curveballs, and the like, are the result of the Magnus Effect which is an aerodymanic (actually a fluid dynamics) effect. No atmosphere, no slice or hook.

Now, Seneca, I would be quite grateful if you could help me with the little matter of the "heavy" ball. How does one resolve the linear and angular forces at work in a spinning sphere, such as a baseball, traveling through space to provide the mathematical/physical explanation for why, of two identical balls traveling at identical linear velocity, the one spinning fastest will be preceived, upon catching it, as "heavier". The angular forces at work are quite small compared to the linear forces and, it seems, should not matter as much as they seem to matter to perception.

And just 'cause I think such things are fun (I never claimed I ain't weird), for many years the clever cleavers and keepers of the laws of aerodynamics searched high and low for some explanation for how bumblebees and such could fly since their wings aren't large enough to generate the lift needed to, well, lift them. Last I checked into this the matter was resolved.

Anybody know the spin on things that 'splains why those lil' beggars can fly?

chuck said...

Anybody know the spin on things that 'splains why those lil' beggars can fly?

Not me. Something to do with vortices, I believe. The wing's motion is also not just up and down. There was a good article some years back but I don't remember where, Scientific American maybe.

You got the basics of it, Chuck. Their wings move not only up and down, but forward and backward. They also flex throughout the range of motion. The aerodynamics are infinitely more complex than those of an airplane wing and, among other forces that haven't yet been adequately modeled, they generate vortices along the the leading edge (and probably the trailing edge also) that, for lack of any better way to articulate it, recycle the airflow over their wings to create greater lift than would be anywhere near possible with rigid wings or simple up and down flapping. It's a bunch of flap-clap stuff ;>

Specter said...

I got a better question - how is the ball going to stay on the tee and does he get a mulligan if it moves during his swing?

Seneca the Younger said...

Knuck --- it's a physiological thing rather than a physics thing, I think. You "measure" weight by deformation of the flesh of the hand. The spinning ball deforms the flesh more because of the angular momentum.

Straight Dope covers the bumblebee question. Here's an easy way to think about it: imagine you're in a pool and treading water. If you just hold your arms out, you sink --- but if you swirl your arms back and forth, you're pushing against the water and that pushes you up. The bumblebee moves its wings back and forth more or less like you move your hands when treading water, rather than like an airplane's wings or a larger bird like a hawk, and "holds itself up".

Seneca the Younger said...

I got a better question - how is the ball going to stay on the tee and does he get a mulligan if it moves during his swing?

Chewing gum.

How he'll get it out of his mouth and onto the tee I leave as an exercise for the reader.

chuck said...

Seneca,

I think the straight dope kinda blows that one. As Knuck points out, the actual aerodynmics is much more interesting than that.

Seneca the Younger said...

Yeah, but there's a limit to what you can write in a newspaper column. Here's another article on using lasers to measure exactly what's going on.

Seneca the Younger said...

Did you know there'ds a bumblebee FAQ ON THE WEB?