The problem of the "sound barrier" has to do with moving through
air, and the things the air does when you try to push it out of the
way faster than the speed of sound. Moving through air faster
than sound was an engineering and technological problem, not
a scientific one.
Concerning light, that's about 874 thousand times faster.
See the problem ?
Answer:

Explanation:
The resistance of a conductor is directly proportional to its length and is inversely proportional to its cross-sectional area, this dependence is given by:

is the material's resistance, L is the legth and A is the cross-sectional area.
For the first and second coils, we have:

For the third and fourth coils, we have:

Answer:
Explanation:
In case of diffraction , angular width of central maxima =2 λ/d
λ is wave length of light and d is slit width
In case of interference , angular width of each fringe
= λ /D
D is distance between two slits
No of interference fringe in central diffraction fringe
=2 λ/d x D/λ = 2 x D /d = 2 x .24/.03 = 16.
The correct answer is circular. Copernicus and other astronomers before him thought that celestial bodies followed a circular orbital path. Copernicus was a Polish astronomer that concluded that the sun is at rest near the center of the universe and the earth is revolving around it annually. This theory is called heliocentric.
Water? The sun. I DUNNO I FEEL BAD :(