00:01
In this problem we have a projectile motion.
00:05
There is this object which is being thrown at some angle theta from the ground with some initial speed v0.
00:15
And this object will travel a distance d in the horizontal direction.
00:22
At this distance there is this wall of fence of height l.
00:29
And when this object reaches at this plane, this one here, we expect it to be at a height age.
00:42
It may be equal to l, it may be lower than l or higher than l.
00:47
So you'll see.
00:49
And everything happens under the action of this gravitational acceleration g.
00:56
Now i have these x and y axis as indicated so that my object starts its motion at the origin just to simplify a certain deal of calculations.
01:13
Now we have a constant velocity motion along the x -axis and constant acceleration motion along the y -axis.
01:25
So let us write down these, write down the equations of kinematics corresponding to these types of motion.
01:36
So x is equal to x0, the initial position plus the initial velocity along the x -axis times t.
01:52
As i have just it, i am setting the origin at the initial position of this object.
01:59
So x0 is equal to 0.
02:02
And this v0 x is just v0 times the cosine of this angle.
02:12
Now we know our v0 and theta values.
02:17
They are 16 meters per second and 40 degrees respectively.
02:24
So using these values, we can write this x in terms of t, as 12 .2567 t.
02:41
So we are going to use the si units throughout these calculations so we don't have to carry around the units everywhere so we know what we are dealing with so that's my point...