Answer:
Because of the presence of air resistance
Explanation:
When an object is in free fall, ideally there is only one force acting on it:
- The force of gravity, W = mg, that pushes the object downward (m= mass of the object, g = acceleration of gravity)
However, this is true only in absence of air (so, in a vacuum). When air is present, it exerts a frictional force on the object (called air resistance) with upward direction (opposite to the motion of free fall) and whose magnitude is proportional to the speed of the object.
Therefore, it turns out that as the object falls, its speed increases, and therefore the air resistance acting against it increases too; as a result, the at some point the air resistance becomes equal (in magnitude) to the force of gravity: when this happens, the net acceleration of the object becomes zero, and so the speed of the object does not increase anymore. This speed reached by the object is called terminal velocity.
<h2>
Answer: By the double slit experiment applied to electrons</h2>
The French physicist Louis De Broglie proposed the existence of matter waves, that is to say that <u>all matter has a wave associated with it.</u>
On the other hand, Heisenberg enunciated the uncertainty principle, which postulates that the fact that <u>each particle has a wave associated with i</u>t, imposes restrictions on the ability to determine its position and speed at the same time.
These postulations were tested with the double slit experiment (formerly applied to photons) applied to electrons, and the result was: electrons (as well as the other particles different from the photons) are able to behave as waves.
The question is asking to describe and state and calculate what do the observer on the earth measure for the speed of the laser beam, and base on my research, the answer would be v = 1bc, I hope you are satisfied with my answer and feel free to ask for more
Hope this answers your questions...
When heat is added to a substance, the atoms and molecules begin to vibrate faster. As that happens the gap between them increases. Opposite happens when cooled, atoms and molecules begin to vibrate slower and the gap between each other decreases. Thus the motion and spacing between atoms signifies the state of matter of the substance.