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Femme_physics
Oct7-10, 03:39 AM
"Meters second ˛ simply means that your velocity will increase by some value every second. For instance, 9.8 m/sec˛ means that your velocity will increase by 9.8 meters per second every second. If you continue to accelerate at that rate, after 10 seconds you'll be moving at 98 meters/second."

G037H3
Oct7-10, 03:50 AM
true, but only until you hit terminal velocity

Femme_physics
Oct7-10, 04:00 AM
So once an object keeps accelerating until it gets to the speed of light and that its terminal velocity?

Dadface
Oct7-10, 04:21 AM
Nothing with mass can reach the speed of light.

Femme_physics
Oct7-10, 04:32 AM
But even electrons have mass, and even waves have particles. So, even they can't reach the speed of light?

Dadface
Oct7-10, 04:35 AM
Particles such as electrons can be accelerated to near light speeds but can't quite reach the speed of light.I think questions of this type have been discussed numerous times on this forum so my advice now is to first do some research here and elsewhere and come back when you have any specific problems.

russ_watters
Oct7-10, 05:39 AM
true, but only until you hit terminal velocity No, this has nothing to do with terminal velocity and your velocity doesn't increase at a constant rate in drag.

russ_watters
Oct7-10, 05:40 AM
So once an object keeps accelerating until it gets to the speed of light and that its terminal velocity? Your first post was fine, but it has nothing to do with terminal velocity and only works for speeds much lower than the speed of light.

For an object accelerating due to gravity from zero speed and a large height, without drag, the maximum speed (the speed you're going when you slam into the ground) is the escape velocity of the earth.

K^2
Oct7-10, 05:29 PM
You pretty much have to disregard relativity for that statement all together. If he is talking about classical physics, it's fine. But once you throw in relativity, things become interesting.

When you are sitting on a surface of a planet, your velocity stays constant, yet according to GR, you are accelerating away from the planet.

But considering nature of the question, I would assume they want a purely classical answer, so none of it matters.

JDługosz
Oct7-10, 07:06 PM
I did some graphs (http://www.dlugosz.com/files/PhysFAQ-edit/Relativity/SR/spaceship_puzzle.html) of that to illustrate Bell's Spaceship Paradox. In SR, you wind up with a hyperbola from constant acceleration in your own frame.