Answer:

Explanation:
A closed system is a system where exists energy interactions with surroundings, but not mass interactions. If we neglect any energy interactions from boundary work, heat, electricity, magnetism and nuclear phenomena and assume that process occurs at steady state and all effects from non-conservative forces can be neglected, then the equation of energy conservation is reduce to this form:
(1)
Where:
- Change in kinetic energy of the system, measured in joules.
- Change in gravitational potential energy of the system, measured in joules.
If we know that
and
, then we get the following equation:
(2)
Where
and
stands for initial and final states of each energy component.
Hence, the right answer is 
Basically its just an air like fluid with chemicals.... just like air it just goes as it pleases and fills space
The centripetal acceleration a is 4.32
10^-4 m/s^2.
<u>Explanation:</u>
The speed is constant and computing the speed from the distance and time for one full lap.
Given, distance = 400 mm = 0.4 m, Time = 100 s.
Computing the v = 0.4 m / 100 s
v = 4
10^-3 m/s.
radius of the circular end r = 37 mm = 0.037 m.
centripetal acceleration a = v^2 / r
= (4
10^-3)^2 / 0.037
a = 4.32
10^-4 m/s^2.
Answer:
16 m/s
Explanation:
Given that
y momentum = 0.080 *25 = 2
x momentum = 0.075*20 = 1.5
total momentum = √(4 + 2.25)
Total momentum = √6.25
Total momentum = 2.5
total mass = mass of x and y momentum = 0.075 + 0.080 = 0.155
speed of mass center = total momentum / total mass = 2.5/0.155 = 16.
And thus, the speed of the center of mass of this two-particle system at this instant is 16 m/s