<span>The magnitude of the rock is equal to g. After the rock is released, there are no more forces acting on it, yet gravity remains. The initial inputs, on a bridge, at an angle of 30 deg below horizontal do not matter after the release.</span>
Answer:
<h2>50 N</h2>
Explanation:
The force required can be found by using the formula

w is the workdone
d is the distance
From the question we have

We have the final answer as
<h3>50 N</h3>
Hope this helps you
Solution :
The motion in the y direction.
The time taken by the toy rocket to hit the ground,

S = distance travelled = 30 m
u = 0 m/s
a = 
t= time in seconds
Therefore, 
t = 2.47 sec
Now motion in the x direction,
u = 12 m/sec

Upon integration 'v' with respect to 't'

Once again integrating with respect to t,


= 0.0176+29.64
= 29.65 m
Therefore, the toy rocket will hit the ground at 29.65 m from the building.
20/9.8 = 2.0 seconds. The ball stops after 2 seconds.