# Homework Help: A lab on one-dimensional collisions

1. Apr 8, 2007

### a seeker

hi, i am doing a lab about analyzing one-dimensional collisions.
There are two synthesis questions that i don't know how to even begin with.

1. How could the results of this investigation be applied to determine the mass of a sealed refuse bag on board the International Space Station? (Everything in the station is under constant free fall.)

First off, i don't even understand the question. what's a 'sealed refuse bag on board the internation space station' anywayz?

2. Adjustable friction pads are available as cart accessories. How would using these pads have affected the results of the collisions in this investigation?

Well, the lab design was to use frictionless carts along a level track, so i think the 'cart' on the question is talking about the one we used. So, how does friction affect 1-D collisions? hmm. i think the friction hinders the movement of the carts, therefore lowering the velocity, which even lowers the values of the cart's momentum and kinetic energy. How's that?

2. Apr 8, 2007

### robb_

I am not clear on the first question.
2. If friction is involved, what happens to the kinetic energy of the carts? Is momentum conserved? (you are on the right track)

3. Apr 9, 2007

### a seeker

omg the first question is killing me!
well, is the Internation Space Station stationary or no?
is it moving? if so, to what direction?
i am trying to derive an equation using
m1v1+m2v2=m1v1'+m2v2' (conservation of momentum).
but i figure this equation alone is not enough.

i am considering
1/2m1v1^2+1/2m2v2^2=1/2m1v1'^2+1/2m2v2'^2 (conservation of energy).
but i can use this equation only when the collision is elastic. but is a collision elastic or inelastic in a space station??
i don't know anything about the space station!!
omg, the question does not specify. what should i do?
anyone knows anything about the space station that can be useful?

Last edited: Apr 9, 2007