Answer: is constant
Explanation:
In order to analyze the velocity of the stars within a galaxy, the <u>galaxy rotation curves</u> (developed by the American astronomer Vera Rubin) are used. These graphs are elaborated as a scatter diagram in which the orbital velocity of the stars present in a galaxy is represented on the Y axis and the distance of these stars to the center of the galaxy on the X axis.
Thanks to this diagram, it has been possible to observe a characteristic behavior in the rotation speed of the stars (and gas) present in the galaxies, which differs from the rules of the orbital movement of the planetary systems postulated by Newton and Kepler.
This means that in these galaxy rotation curves it has been observed that the rotation speed of stars and gas is "constant", regardless of the distance to the center of the galaxy. This discrepancy and these results were then used to demonstrate the existence of dark matter in the universe.
Answer:
1.B 2.A,C,D
Explanation:
A mineral is a naturally occurring, inorganic compound with a unique chemical structure and physical properties. A rock is a solid, stony mass composed of a combination of minerals or other organic compounds. For example, quartz and feldspars are minerals, but when formed together, they make a rock, granite.
Radiation and deaths of people
Because of genetic variation
Answer:
Wind Shear is the difference in direction and speed of the wind in the atmosphere within a specific distance.
Explanation:
Eddies are generated when winds goes over a mountain creating vertical shear on the side that is sheltered from it, that creates air pockets causing atmospheric turbulence know as "rotors".
The change of direction and wind speed with altitude variation is called Vertical wind shear.
The change in wind speed together with a change in lateral position at a certain altitude is called Horizontal wind shear.
One scenario is a mountain with down-bursts and micro-bursts creating ice crystal plumes clouds that could warn pilots of wind shear, allowing then to avoid accidents.
