Answer:
Center of mass lies 24 m in front of center of mass of second wagon.
Explanation:
Suppose A 1200 kg station wagon is moving along a straight highway at 12.0 m/s. Another car with mass 1800 kg and speed 20.0 m/s.
Given that,
Mass of first wagon = 1200 kg
Mass of second wagon = 180 kg
Distance = 40 m
We need to calculate the position of the center of mass of the system
Using formula of center mass



Hence, Center of mass lies 24 m in front of center of mass of second wagon.
According to Newton's second law, the resultant of the forces acting on the box is equal to the product between its mass and its acceleration:

(1)
we are only concerned about the horizontal direction, so there are only two forces acting on the box in this direction:
- the horizontal component of the force exerted by the rope, which is equal to

- the frictional force, acting in the opposite direction, which is equal to

By applying Newton's law (1), we can calculate the acceleration of the box:

As this mechanical energy is associated with height, it would be "Potential Energy" in particular.
U = mgh
U = F.h
U = 1.5 * 4
U = 6 Joules
So, 6 J of energy is lost before it hits the ground.
Hope this helps!
a. A dam is usually built at the site of hydroelectric power. As water accumulates, its potential power for producing electric power increases. As this water moves downstream from the dam, mostly through a fall, its kinetic energy is harnessed by turbines and converted to electric energy.
b. One factor is the height of the fall of the water from the dam. The higher the height the higher the kinetic energy of the water and hence can be converted to higher electric energy. The higher the number of coils of the turbine generator being rotated by the water, the higher the conversion to electric current.
c. One is impoundment. This type is the most common and involves the building of a dam to store water and later the water is released to turn turbines. The second type is diversion. This type does not require a dam. Some water is diverted from the main river to create a pen-stock that runs a turbine.
d. The advantage of hydroelectric power is that is is a clean energy source hence does not cause global warming. Global warming can have economic consequences. The operating cost of this type of plant is low hence the costs of electricity are able to be kept low for the consumers. 2 disadvantage is that creating a dam upstream causes a change in the physical and chemical characteristics of the river or water bodies affecting ecosystems. Another is that electricity is dependent on the water regime hence dependency is tied to climate.
Answer:
option C
Explanation:
given,
mass of the three planet is same
radius of the planets are
R₁ > R₂ > R₃
expression of escape velocity

G is the gravitational constant
M is the mass of the planet
R is the radius of the planet
from the above expression we can clearly conclude that the escape velocity is inversely proportional to the radius of the Planet.
radius of planet increases escape velocity decreases.
Hence planet 3 has the smallest radius so the escape velocity of the third planet will be maximum.
The correct answer is option C