Answer:
Explanation:
Evolution is both a fact and a theory. Evolution is widely observable in laboratory and natural populations as they change over time. The fact that we need annual flu vaccines is one example of observable evolution. At the same time, evolutionary theory explains more than observations, as the succession on the fossil record. Hence, evolution is also the scientific theory that embodies biology, including all organisms and their characteristics. In this paper, we emphasize why evolution is the most important theory in biology. Evolution explains every biological detail, similar to how history explains many aspects of a current political situation. Only evolution explains the patterns observed in the fossil record. Examples include the succession in the fossil record; we cannot find the easily fossilized mammals before 300 million years ago; after the extinction of the dinosaurs, the fossil record indicates that mammals and birds radiated throughout the planet. Additionally, the fact that we are able to construct fairly consistent phylogenetic trees using distinct genetic markers in the genome is only explained by evolutionary theory. Finally, we show that the processes that drive evolution, both on short and long time scales, are observable facts.
Answer:
0.056 psi more pressure is exerted by filled coat rack than an empty coat rack.
Explanation:
First we find the pressure exerted by the rack without coat. So, for that purpose, we use formula:
P₁ = F/A
where,
P₁ = Pressure exerted by empty rack = ?
F = Force exerted by empty rack = Weight of Empty Rack = 40 lb
A = Base Area = 452.4 in²
Therefore,
P₁ = 40 lb/452.4 in²
P₁ = 0.088 psi
Now, we calculate the pressure exerted by the rack along with the coat.
P₂ = F/A
where,
P₂ = Pressure exerted by rack filled with coats= ?
F = Force exerted by filled rack = Weight of Filled Rack = 65 lb
A = Base Area = 452.4 in²
Therefore,
P₂ = 65 lb/452.4 in²
P₂ = 0.144 psi
Now, the difference between both pressures is:
ΔP = P₂ - P₁
ΔP = 0.144 psi - 0.088 psi
<u>ΔP = 0.056 psi</u>
Answer: 6,400 km
Explanation:
The weight of a person is given by:
where m is the mass of the person and g is the acceleration due to gravity. While the mass does not depend on the height above the surface, the value of g does, following the formula:
where
G is the gravitational constant
M is the Earth's mass
r is the distance of the person from the Earth's center
The problem says that the person weighs 800 N at the Earth's surface, so when r=R (Earth's radius):
(1)
Now we want to find the height h above the surface at which the weight of the man is 200 N:
(2)
If we divide eq.(1) by eq.(2), we get
By solving the equation, we find:
which has two solutions:
--> negative solution, we can ignore it
--> this is our solution
Since the Earth's radius is 
, the person should be at 
above Earth's surface.
Answer:9.8 m/s²
Explanation:
It was going at 9.8m/s² as this is the acceleration of an object due to gravity
when an object falls it accelerates at a consant and uniform speed which is 9.8m/s²
Answer:
0.384c
Explanation:
To find the speed of the pursuit ship relative to the cruiser you use the following relativistic equation:
u': relative speed
u: speed of the pursuit ship = 0.8c
v: speed of the cruiser = 0.6c
c: speed of light
You replace the values of the parameters to obtain u':
Hence, the relative speed is 0.384c
