Reaction force is on the person in backward direction
Explanation:
When we throw the ball then the action force is on the ball due to which ball is pushed away with certain velocity.
Here the reaction force is of same magnitude but in opposite direction on us due to which we pushed back.
Here we do not move in backward direction because here the force on us is counterbalanced by the friction force of the ground due to which we can maintain our position easily.
So here we can say that action and reaction pair are the two forces of equal magnitudes but opposite in direction.
One force here is action force on ball then the reaction force is on the person who throw the ball
Asexual reproduction produces offspring that are genetically identical to the parent because the offspring are all clones of the original parent. During sexual reproduction the genetic material of two individuals is combined to produce genetically diverse offspring that differ from their parents.
Assuming no other forces acting on the rock, since the accelerarion due to gravity close to the surface to the Earth can be taken as constant, we can use one of the kinematic equations in order to get first the maximum height (over the roof level) that the ball reaches:
Taking into account that at this point, the speed of the rock is just zero, this means vf=0 in (1), so replacing by the givens and solving for Δh, we get:
So, we can use now the same equation, taking into account that the initial speed is zero (when it starts falling from the maximum height) and that the total vertical displacement is the distance between the roof level and the ground (26.0 m) plus the maximum height that we have just found in (2) , 14.8m:
Δh = 26.0 m + 14. 8 m = 40.8 m (3)
Replacing now in (1), we can solve for vf, as follows:
B)
In order to find the total elapsed from when the rock is thrown until it hits the street, we can divide this time in two parts:
1) Time elapsed from the the rock is thrown, until it reaches to its maximum height, when vf =0
2) Time elapsed from this point until it hits the street, with vo=0.
For the first part, we can simply use the definition of acceleration (g in this case), making vf =0, as follows:
Replacing by the givens in (5) and solving for Δt, we get:
For the second part, since we know the total vertical displacement from (3), and that vo = 0 since it starts to fall, we can use the kinematic equation for displacement, as follows:
Replacing by the givens and solving for t in (7), we get: