Answer:
a) It is moving at 
when reaches the ground.
b) It is moving at 
when reaches the ground.
Explanation:
Work energy theorem states that the total work on a body is equal its change in kinetic energy, this is:
(1)
with W the total work, Ki the initial kinetic energy and Kf the final kinetic energy. Kinetic energy is defined as:
(2)
with m the mass and v the velocity.
Using (2) on (1):
(3)
In both cases the total work while the objects are in the air is the work gravity field does on them. Work is force times the displacement, so in our case is weight (w=mg) of the object times displacement (d):
(4)
Using (4) on (3):
(5)
That's the equation we're going to use on a) and b).
a) Because the branch started form rest initial velocity (vi) is equal zero, using this and solving (5) for final velocity:
b) In this case the final velocity of the boulder is instantly zero when it reaches its maximum height, another important thing to note is that in this case work is negative because weight is opposing boulder movement, so we should use -mgd:
Solving for initial velocity (when the boulder left the volcano):
The gravitational force between the objects A. It would increase.
Explanation:
The magnitude of the gravitational force between two objects is given by:
where
G is the gravitational constant
are the masses of the two objects
r is the separation between the objects
In this problem, we are told that one of the object (the one on the right) gains mass: this means that, for instance, the value of 
increases. We can see from the equation that the gravitational force is directly proportional to the masses: therefore, if one of the masses increases (while the distance between the two objects remains constant), it means that the force also increases.
Therefore, the correct answer is
A. It would increase.
Learn more about gravitational force:
brainly.com/question/1724648
brainly.com/question/12785992
#LearnwithBrainly
Answer:
Note that:
Particles in a:
gas are well separated with no regular arrangement.
liquid are close together with no regular arrangement.
solid are tightly packed, usually in a regular pattern.
Explanation:
The animals need less food people it is winter time.
A=F/m
a=(3000000)/(20000)
a=15 m/s^2
