00:01
Now in this question, you have a plate, you have a plate like this, and this is a ground, and this plate dropped vertically on the ground and became a few pieces, right? so if you look at ground, a few pieces, some pieces going one way, some people are going the other way, three pieces, okay? and another, we're going the other way, okay? i'm going to better sketch this situation.
00:27
Now the first question asks, what is the horizontal momentum of the plate just before it smashed by zero, right? because just before it was smashed, the plate has no velocity or not the horizontal direction, right? it's just going downward.
00:43
So the horizontal direction velocity is zero.
00:46
The horizontal velocity is zero.
00:48
So the horizontal momentum is all zero.
00:50
So i would say px equals zero.
00:52
Okay, suppose this is the x direction.
00:54
So the horizontal momentum is zero.
00:56
And of course, you know that the momentum has to be conserved horizontally.
01:00
So you look at the three pieces and the total momentum of the three pieces put together the master zero, right? so let's look at these three fragments.
01:09
The first fragment says going at an angle west of north.
01:14
So let me try to draw that.
01:16
On this sketch, let me try to erase with only this sketch.
01:21
So let's look at the first segment, which is go ahead.
01:26
Going west of north, right? so let me try to draw the directions like this.
01:34
So this is the east, this is the west, the north, the source.
01:39
So one of the fragment goes to west of north...