Because dark line spectra result from passing white light through ionized gasses and plasmas, which is what the atmosphere of stars are made of. These frequencies are scattered by the star's atmosphere as it leaves the surface (photosphere) of the star, and don't make it to earth.
Answer:
11 kilometers (7 miles) per second, or over 40,000 kilometers per hour (25,000 miles per hour)
Explanation:
Answer:
1.It's the world's most famous equation, but what does it really mean? "Energy equals mass times the speed of light squared." On the most basic level, the equation says that energy and mass (matter) are interchangeable; they are different forms of the same thing.
2.The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei.
3.In nuclear reactions, mass is never conserved—some mass is exchanged for energy and energy for mass. Nuclear reactions take place in an atom's nucleus. In a spontaneous nuclear reaction, such as radioactive decay, mass is "lost" and appears as energy in the form of particles or gamma rays.
4.In a nuclear reaction, mass decreases and energy increases. The sum of mass and energy is always conserved in a nuclear reaction.
5.The process releases energy because the total mass of the resulting single nucleus is less than the mass of the two original nuclei.
Explanation:
hope it helps
Answer:4.39 s
Explanation:
Given
initial velocity 
acceleration 
velocity acquired by sled in 
time
distance traveled by sled in 
distance traveled in 
time with velocity
----1
substitute the value of in 1
we get
thus 
(Direction) for the fact that it will continue having the momentum at the constant speed in which the engines turned off.
