Moon....

[asterroc]

My students this semester found this question more challenging than they usually do. It's small number statistics and all, but I'm curious what y'all think. Please answer before viewing other people's answers, and if you care to explain your reasoning in the comments, I'd love to see.

[Poll #1918673]

Comments

[meig.livejournal.com]

There is gravity on the moon, but less than on the Earth, so the pencil will be pulled toward the ground. I think it will fall more slowly, but due to the fact that there is no atmosphere to slow it down, it may actually fall more quickly. But I think that since there is also pull from the Earth, it will fall more slowly. I've never really explored this concept or thought hard on it, though.

[sildra.livejournal.com]

The slowing effects of the atmosphere on Earth are actually very small on something the size and shape of a pencil, until you get to very high speeds. Meanwhile the moon is orbiting the Earth, which is equivalent to being in free fall, so something on the surface of the moon doesn't experience gravity from Earth (except as a tidal force). So the only non-negligible consideration is the first one you said: that there is gravity on the moon, but less than on Earth, so the pencil will fall but more slowly.

(Also, Earth's gravity would pull in the opposite direction of the moon's gravity on the side of the moon facing the Earth, but on the far side of the moon it would be pulling in the same direction.)

[hrafn.livejournal.com]

I could answer this as I did because I remember what footage of astronauts bouncing around on the moon looks like. Slo. Mo. Tion.

[calzephyr77.livejournal.com]

There's also a video out there of astronauts dropping a hammer and a feather :)

[tiurin.livejournal.com]

HEAVY BOOTS!

[blahblahboy.livejournal.com]

If I read it hastily and did one of those "read options until you find a plausible answer and stop reading the rest of the options" I might have gone for C. What kind of answer distribution did you wind up getting?

[zandperl.livejournal.com]

Half said hang where you let go and half said float away from the Moon's sfce. This semester the discussion group related to this backfired horribly, with one student deciding there was no gravity on the Moon and convincing everyone else. First time I've had peer instruction go so poorly.