Answer:
The alternative energy sources are defined as those resources that are used in place of the natural and non-renewable resources. This resources plays an important role in the conservation of natural resources.
The fossil fuels are the resources on which the people are directly dependent. Burning up of these fossils leads to the emission of carbon, which has a direct impact on earth. A small increase in the amount of carbon dioxide can lead to the increase in the surface temperature of earth.
In addition to this, these fossil fuels such as coal, petroleum, oil and natural gases are found to be present in a limited proportion, and it is a very expensive process to obtain these resources, so sustainable development method must be adopted in order to save this natural resources for the future generation.
Some of the examples of alternative resources that are widely used in place of fossil fuels are wind energy, solar energy, tidal energy, biomass energy and bio-fuels.
Thus, it is very important to develop and use alternative resources.
Answer:
26.9 Pa
Explanation:
We can answer this question by using the continuity equation, which states that the volume flow rate of a fluid in a pipe must be constant; mathematically:
(1)
where
is the cross-sectional area of the 1st section of the pipe
is the cross-sectional area of the 2nd section of the pipe
is the velocity of the 1st section of the pipe
is the velocity of the 2nd section of the pipe
In this problem we have:
is the velocity of blood in the 1st section
The diameter of the 2nd section is 74% of that of the 1st section, so

The cross-sectional area is proportional to the square of the diameter, so:

And solving eq.(1) for v2, we find the final velocity:

Now we can use Bernoulli's equation to find the pressure drop:

where
is the blood density
are the initial and final pressure
So the pressure drop is:

Answer:
His machine must increase
Explanation:
Answer:
(A) 2.4 N-m
(B) 
(C) 315.426 rad/sec
(D) 1741.13 J
(E) 725.481 rad
Explanation:
We have given mass of the disk m = 4.9 kg
Radius r = 0.12 m, that is distance = 0.12 m
Force F = 20 N
(a) Torque is equal to product of force and distance
So torque
, here F is force and r is distance
So 
(B) Moment of inertia is equal to 
So 
Torque is equal to 
So angular acceleration 
(C) As the disk starts from rest
So initial angular speed 
Time t = 4.6 sec
From first equation of motion we know that 
So 
(D) Kinetic energy is equal to 
(E) From second equation of motion

Answer:
At 2km/h*s it is changing speed every 2 seconds.
At 4km/h*s it is changing speed every 4 seconds.
At 10km/h*s it is changing speed every 10 seconds.