<span>The initial momentum of the boy is equal to the boy/boat because the final velocity of the boat is less than the initial velocity of the boy.</span>
The correct answer is (a.) Hydra. Hydra is not a dwarf planet, instead, it is the moon of the dwarf planet, Pluto. There are only four accepted dwarf planets by the International Astronomical Union which were the Haumea, Pluto, Eris, and Makemake.
Answer:
v = 79.2 m/s
Solution:
As per the question:
Mass of the object, m = 250 g = 0.250 kg
Angle, 
Coefficient of kinetic friction, 
Mass attached to the string, m = 0.200 kg
Distance, d = 30 cm = 0.03 m
Now,
The tension in the string is given by:
(1)
Also
T = m(g + a)
Thus eqn (1) can be written as:





Now, the speed is given by the third eqn of motion with initial velocity being zero:

where
u = initial velocity = 0
Thus


Given :
You fire a paintball from a paintball gun straight up into the air at 25.0 m/s.
To Find :
What is the ball velocity at the higher point that the ball reaches.
Solution :
We know, when ball is moving upward acceleration due to gravity is applied downward.
So, the ball will decelerate and when ball reaches maximum height its velocity will become zero.
Therefore, ball velocity is 0 m/s at maximum height.
Hence, this is the required solution.