Answer:
Resistivity ρ=1.12 x 10^-4 Ωm
Explanation:
ρ= RA/l, where R is resistance, A is cross sectional area and l is length
A=πr^2
Note Current is given R is proportion to temperature and inversely proportional to Current R=(20+273)/14*10^-2 =2000Ω
⇒ρ=R*πr^2/l all length in metre.
Reduce friction because friction just makes things harder
Answer:
As the planets are very small and dark in comparison with stars, it makes them very hard to be found from earth.
Explanation:
Astronomy, of course, has a solution for this. As astronomers can't observe planets directly, they decided to observe the stars and search for the effects that planets have on them.
There are many ways of observing the exoplanets: Radial Velocity, Transit Photometry, Microlensing, Astrometry, Direct Imaging, etc.
Before all of this, scientist had to find ways to prove their theories. Most of their time they have spent in giving the creative answers.
Science and creativity are very much connected when we speak about the development of science. Rationality and creativity always go together.
In order to create an idea that other people will consider useful, it is important to use creativity. As no one has the exact answer when it comes to science, the adventure is to research the unknown.
To solve this problem it is necessary to apply the concepts related to the conservation of energy, through the balance between the work done and its respective transformation from the gravitational potential energy.
Mathematically the conservation of these two energies can be given through
Where,
W = Work
Final gravitational Potential energy
Initial gravitational Potential energy
When the spacecraft of mass m is on the surface of the earth then the energy possessed by it
Where
M = mass of earth
m = Mass of spacecraft
R = Radius of earth
Let the spacecraft is now in an orbit whose attitude is 
then the energy possessed by the spacecraft is
Work needed to put it in orbit is the difference between the above two
Therefore the work required to launch a spacecraft from the surface of the Eart andplace it ina circularlow earth orbit is
What are the choices? hydro relates to water, power, and furnishing water
