Special relativity has become a fundamental theory in the 20th century and is crucial for explaining many astrophysical phenomena. A central aspect of special relativity is the transformation from one reference frame to another. The following Lorentz transformation matrix gives the transformation from a frame at rest to a moving frame with velocity v along the z-axis:

γ 0 0 γβ
0 1 0 0
0 0 1 0
γβ 0 0 γ

where β = v/c with c being the speed of light in a vacuum, and γ is the Lorentz factor:
γ =
1
p
1 − β
2
(a) State and explain the two traditional postulates from which special relativity originates.
(b) Draw a plot of the Lorentz factor for 0 ≤ β ≤ 0.9 to see how its value changes.
One of the many exciting phenomena of special relativity is time dilation. Imagine astronauts
in a spaceship that is passing by the Earth with a high velocity.
(c) Are clocks ticking slower for the people on Earth or for the astronauts on the spaceship?
(d) How fast must the spaceship travel such that the clocks go twice as slow?

their crystal patterns have been disrupted by stress

a is the best answer your welcome

the only real purpose of sputnik 1 was to beat the us into space. we were getting close to launching a useful satellite, explorer 1 - which launched on january 31, 1958. the ussr had to beat that, so they launched sputnik 1 on october 4, 19

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia