Answer:
D.
Explanation:
acceleration in the z component = velocity in z component / time. The question states velocity in z component is zero. Therefore, acceleration in z component = 0/time = 0.
Now the question does not specify whether the other velocity vectors (x or y) is zero or not. So its D.
The correct answer is
<span>C) -10.7 m/s
In fact, the first rock is moving upward with velocity +4.5 m/s, while the second rock is moving downward with velocity -6.2 m/s, with respect to a fixed reference frame. In the reference frame of the first rock, instead, the second rock is moving with velocity equal to its velocity in the fixed frame minus the velocity of the reference frame of the first rock:
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Answer:
Explained in Depth.
Explanation:
It is all matter of what kind of stars are we talking about, for simplicity let's say we are talking about normal stars such as our sun.
If there is a molecular cloud that has a mass that is slightly larger than our sun then it is possible that the gravity will eventually pull together cloud into a sphere that would have enough mass to start nuclear fusion which is important to become a star.
Mass of such cloud would be 1.98x10^30Kg almost equal to the sun's mass.
All of this implies that stars are formed when there is enough mass to let gravity pull it all together into a sphere that has enough gravitational pull to start nuclear fusion inside the core.
Backlighting is used to create silhouettes
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