00:01
Number 15, we're looking down on earth, like an overhead view.
00:05
Somebody's sitting here, and then somebody else is flying directly over them in the southeast direction with a speed of 100.
00:21
And then five seconds later, a firecracker that's 200 meters over this way.
00:28
From there, explodes.
00:35
And we want to know where that firecracker is.
00:39
With respect to where this flying person is.
00:44
And that firecracker went off five seconds later.
00:48
Well, if it was five seconds later, if this is going 100 meters per second, after five seconds, this will have gone 500 meters.
00:57
And it said that it was going southeast.
00:59
So i'm taking this to be exactly southeast in the middle here.
01:03
So this is a 45 degree angle.
01:04
This is a 45 degree angle.
01:06
I can find these.
01:09
I can find.....