00:01
In this problem, we have been given that there is a model rocket which is fired from rest in the vertically upward direction.
00:09
And the acceleration of this rocket is constant, that is, 16 .6 meter per second square, for a time interval of 1 .2 seconds.
00:20
And this rocket's fuel gets exhausted.
00:24
Let's say at this point p, its fuel is exhausted, and definitely it will move a little distance.
00:31
Up as well because it stated that from the point its fuel is exhausted, it's in free fall, and we are required to determine the vertical distance which this rocket travels.
00:42
So here we see that there are two parts of journey, one from the point where the rocket is projected to the point p where its fuel is exhausted.
00:51
And we have the parameters, initial velocity, time, and acceleration.
00:56
Let's use them and find out the distance from the point of projection to the point.
01:01
The point p so we'll use this kinematic equation and when we put the values we get s coming out to be ut which is zero plus half a t square that's 8 .3 into t squared that's 1 .2 square so when we square 1 .2 and to this we multiply 8 .3 we're going to get 11 .952 meters and let's find out the velocity of the rocket at this point p by using this expression.
01:31
So when we put the values we get we as u plus 80, that's just 16 .6 times 1 .2.
01:39
And when we multiply 16 .6 with 1 .2, we get we coming out to be 19 .92 meter per second...