00:01
All right, hello! so in this question we're given information about two ice skaters who push off of one another.
00:07
We have jeff who has a mass of 80 kilograms and after blythe pushes off of him, he is moving in my diagram here to the right at a speed of 4 meters per second.
00:22
And the question asks what is the speed of blythe after she is pushed off.
00:28
So in part a we're looking for the conservation momentum.
00:36
So our final momentum as a vector is going to equal our initial momentum.
00:40
Because everything is in one plane here, we don't really have to worry too much about the vector step.
00:46
Initially neither person is moving, so we're going to have zero momentum initially.
00:52
And at the end we're going to have the mass of blythe times the velocity of blythe minus, because we're moving in opposite directions, the mass of jeff times the velocity of jeff.
01:07
And so after they push apart, their momentums will be equal...