1
00:00:01,380 --> 00:00:17,220
So we know from our displacement equation that is is is zero plus v0 t plus a half a D squared.

2
00:00:17,520 --> 00:00:18,710
OK, we have to wrap that.

3
00:00:18,720 --> 00:00:20,190
So this gives us our position.

4
00:00:20,580 --> 00:00:23,820
It says our position is equal to our initial position.

5
00:00:26,720 --> 00:00:35,600
Plus, our initial velocity times, time plus of acceleration multiplied by time, squared off a projectile

6
00:00:35,600 --> 00:00:41,900
motion, we can use this, we can use this equation, we just need to substitute the appropriate values

7
00:00:41,900 --> 00:00:42,550
properly.

8
00:00:42,950 --> 00:00:44,990
So a projectile

9
00:00:48,080 --> 00:00:55,040
will typically move in the extra direction and in the Y direction.

10
00:00:55,340 --> 00:00:59,270
You can imagine if you throw a stone, it'll move in the direction.

11
00:01:00,640 --> 00:01:01,100
OK.

12
00:01:01,750 --> 00:01:07,390
And it'll also move in the one direction will go up and then it'll come down again under the influence

13
00:01:07,390 --> 00:01:08,140
of gravity.

14
00:01:08,770 --> 00:01:14,440
So our acceleration that'll be G now gravity works.

15
00:01:17,480 --> 00:01:20,870
To the center of earth, so we're going to take that as negative.

16
00:01:22,290 --> 00:01:30,420
And so we consider each direction separately, so let's first look at the X direction, i.e. the horizontal

17
00:01:30,930 --> 00:01:32,400
motion of a projectile.

18
00:01:37,890 --> 00:01:46,200
OK, so horizontally we can say X or expositional is going to be X euro compared with this equation.

19
00:01:48,360 --> 00:01:53,730
And we are going to say that our initial velocity.

20
00:01:56,450 --> 00:02:00,620
Is V0 in the X direction?

21
00:02:02,670 --> 00:02:04,890
OK, multiplied by the.

22
00:02:07,640 --> 00:02:12,860
We don't have any acceleration in the X direction, so that's going to be zero.

23
00:02:13,960 --> 00:02:22,820
So, yes, our displacement in the X direction for a Y direction, we can say that we have our initial

24
00:02:22,820 --> 00:02:24,050
position in the Y.

25
00:02:28,200 --> 00:02:34,830
Plus, now compare that with this V zero and the wind direction multiplied by T, and now I'm going

26
00:02:34,830 --> 00:02:38,520
to substitute minus G minus nine point eight one.

27
00:02:39,650 --> 00:02:48,950
For a so it's going to be minus one over to G d squared, and I can also find a velocity in the right

28
00:02:48,950 --> 00:02:55,430
direction, but just taking the derivative of the position in the X direction so I can say the velocity

29
00:02:55,430 --> 00:02:58,940
in the direction that is going to be all this is a constant.

30
00:02:58,940 --> 00:03:04,490
So that allows you to take the derivative automative that becomes zero sum.

31
00:03:04,880 --> 00:03:14,240
And then we are left with the zero in the Y direction and we are left with minus and I multiply there,

32
00:03:15,120 --> 00:03:18,050
so I get minus G t.

33
00:03:18,530 --> 00:03:20,920
So that is our velocity in the water section.

34
00:03:22,820 --> 00:03:28,190
And so this is a nice application of our equation of motion for projectile motion.