Initial speed = 2√10 m/s
<h3>Further explanation </h3>
Linear motion consists of 2: constant velocity motion with constant velocity and uniformly accelerated motion with constant acceleration
An equation of uniformly accelerated motion
V = vo + at
Vt² = vo² + 2a (x-xo)
x = distance on t
vo / vi = initial speed
vt / vf = speed on t / final speed
a = acceleration
vf=20 m/s
d = 60 m
a = 3 m/s²
Models show how the atoms in a compound are connected.
The correct answer is - A. Plants store solar energy; the plants die; the plants are compressed; solar energy is released;
The plants use the solar energy for their functioning, thus they are one of the biggest natural storage of it. The plants also use the CO2 for the process of photosynthesis that is driven by the solar energy. When the plants die, the things inside them are stored in them, and if they are quickly covered they will remain stored and not get back into the atmosphere. The plants than are compressed, and over time that leads to a change in their composition. After millions of years had passed, the solar energy and CO2 had turned into coal. The coal is heavily used by the humans in the past few centuries, and with its burning the solar energy and the CO2 are released back into the atmosphere from which they came millions of years ago.
The higher density allows the protogalactic clouds to cool faster and form an elliptical galaxy rather than a spiral galaxy.
In physical cosmology, a protogalaxy or protogalactic cloud , which could also be called a "primeval galaxy", is a cloud of gas which is forming into a galaxy. It is believed that the rate of star formation during this period of galactic evolution will determine whether a galaxy is a spiral or elliptical galaxy; a slower star formation tends to produce a spiral galaxy. The smaller clumps of gas in a protogalaxy form into stars.
Composition
Since there had been no previous star formation to create other elements, protogalaxies would have been made up almost entirely of hydrogen and helium. The hydrogen would bond to form H2 molecules, with some exceptions. This would change as star formation began and produced more elements through the process of nuclear fusion.
Mechanics
Once a protogalaxy begins to form, all particles bound by its gravity begin to free fall towards it. The time taken for this free-fall to conclude can be approximated using the free-fall equations. Most galaxies have completed this free-fall stage to become stable elliptical or disk galaxies, the disks taking longer to fully form. The formation of galaxy clusters takes much longer and is still in progress now.
This stage is also where galaxies acquire most of their angular momentum. A protogalaxy acquires this due to gravitational influence from neighbouring dense clumps in the early universe, and the further the gas is away from the centre, the more spin it gets.
Learn more about protogalactic clouds here : brainly.com/question/28166070
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