00:01
So this is the condition, this is ball 1 and this is ball 2.
00:04
And let's suppose that the initial speed of the ball 2 is u in upward direction.
00:08
We are given that that they meet at this point p, which is 60 meters from the ground.
00:13
Now the time taken by ball 1 to which this point p would be cost to what? first of all, the displacement for ball 1 in the wide direction would be because to 90 meters.
00:24
The acceleration due to gravity is equal to for ball 1, it would be equal to positive 9 .8 meter per second.
00:31
Square the reason is that the gravity is supporting the motion of ball one okay let's say it's say that time it time taken by ball is small t so now let's apply the equation of motion that is s y is equal to uy t plus half a y t square and this is for the ball one sorry for this is for the ball one and we know that for ball one initial speed is zero so that means we can say that s y which is 90 is equal to 1 by 2 times of a which is 9 .8 t square so the time taken by the ball is equal to 180 divided by 9 .8 to the square root okay so now let's find out this value that is square root of a square root of this term is equal to approximately 4 .3 seconds so this is the time taken by the ball 1 and this would be the time taken by ball 2 to reach to the point p to reach to point p as well.
01:39
Now for the ball two, the displacement is equal to positive 60 meters if you are taking the upward action positive.
01:46
And the acceleration for this ball would be negative because now the gravity is opposing its motion...