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Hello.
00:02
In this problem, we have a hoax that is 200 meters above the ground where it's holding a mouse.
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At the first instant, the mouse escaped from the hoke and started to fall towards the ground.
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And after two seconds, the hook kept moving in its direction.
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So here, this is after two seconds, where the mouse kept falling.
00:31
And then the hook noticed this and started to move towards the mouse and she caught him where he was just three meters above the ground.
00:47
Of course the mouse kept moving in a projectile motion until it reached this position.
00:54
So if the hook moved in a straight line, what is the speed and the direction of the hook in this case? so let's start our analysis first by knowing after two seconds what happened.
01:19
So after two seconds, let's start.
01:25
After two seconds, the mouse's velocity in the x direction, ignoring the air resistance is just 10 meters per second as exactly the velocity of the holder, which is the hook.
01:40
And his y velocity is unknown at this point, and his height is unknown as well.
01:53
So let's get the height.
01:55
The height is always v .t.
01:57
T plus half a t squared.
02:01
In that case, the initial velocity in the y direction is zero, because he simply released himself, and a here stands for the gravitational acceleration, which is 9.
02:14
0 .8 times t squared.
02:17
T squared here we can replace it by 2 so that's 2 squared which is 4 so that's equal to 19 .6 meters downward from where he were originally so that this distance is 19 .6.
02:42
Starting from here let's know after what time did the mouse reach 3 meters above above the ground.
02:56
So again, let's substitute in that equation, but we put y here, the distance.
03:06
It needs to cross until it reach this height is 197 meters because we're calculating from 200 meters already.
03:17
So here we have 197 is equal to v .t again, v .0 is 0.
03:24
So this is equal to half a t squared.
03:28
So t is basically the square root of 197 divided by half multiplied by the gravitational acceleration, and that's 6 .3 .4 seconds...