00:01
We are looking for the initial speed of a panther that jumps at an angle of 42 degrees, and it can reach a maximum height of 2 .55 meters.
00:11
We want to know what is this speed that it launches itself at.
00:15
And so we're going to use the vertical information for this projectile motion problem.
00:19
We know our height is 2 .55.
00:21
This is our maximum height.
00:23
Velocity in the y at maximum height, or in the vertical, is simply zero.
00:28
It is still moving over, but it's no longer moving up.
00:33
We know that the acceleration due to gravity is negative 9 .8 meters per second squared, because we're going to assume this is on earth.
00:42
And so this gives us all the information we need to solve for initial velocity in the vertical direction.
00:49
And so we're going to use the equation, be final squared.
00:52
It's equal to the initial squared plus two times acceleration times distance.
00:57
This is simply zero.
01:00
And so we're going to subtract this from both sides, and we get v initial squared is equal to 2 times acceleration times distance.
01:10
And this is negative because we subtracted it from both sides...