OT: The 10th Demention

[AgentZero]

Something's amiss with the Work formula. If I lift a brick straight up it takes some effort. If I lower that brick straight down, it doesn't feel like I've exerted as much effert. If I push it sideways on a slippery surface, it takes almost no effort at all.

I only got a C in highschool physics, so I'm no expert, but the way I remember it working is this: When you lift the brick, you're working against gravity, so you personally do most of the work, so it seems hard. When you lower the brick, gravity is doing most of the work, so to you it seems easy. But either way, the same amount of work is being exerted on the brick. I think the work formula by itself is based on moving things through the air, and you have to make additional calculations for friction when you're moving an object across a surface. Or something. I was sick when we covered friction so I'm kinda fuzzy on it.

What if I tossed a steel marble up in a vacuum sealed metal box here on earth? Would it continue to bounce up to some specific height?

Things stop bouncing because every time they hit the object they're bouncing against, they transfer some of their energy into what ever they're bouncing against, so your marble would probably bounce just the same in a vacuum as it does in the atmosphere, since air friction plays a very small part in slowing the marble. Otherwise, air being thin as it is, things would bounce for a very long time!