The construction of Old Fort Jackson was ordered by Thomas Jefferson, the US president at the time, as a part of a defense system he has planned for the new country. It's location on the river was crucial and its purpose was to ensure that no enemy forces would travel to the inland through the river. At the time an attach from Great Britain or France seemed likely and it was with those two powers in mind that th Fort was built.
Answer:
A. A shift in the way a river flows
Explanation:
The object must move with the speed of times to approximately seeing that it is contracted to exactly half of its actual length.
<h3>How is this calculated?</h3>
The length contraction experimented by the object as it approaches lightspeed, in meters per second, is described by Lorentz contraction formula:
Here, v is the current speed m/s
c is the speed of light in m/s
L' is the length of the object at rest in m
L is the length of the object at the current speed in m
Now we know that
and then,
Hence, r =
Therefore, the answer is the object must travel at a speed of times the lightspeed to be contracted to one-half its proper length.
To know more about the Lorentz contraction formula, visit:
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