Answer:
A. velocity has a direction .. .
with magnitude too but speed has only magnitude
Answer: Within any frame of reference that is accelerating
Special relativity was proposed on 1905 by Einstein, who developed his theory based on the following two postulates:
1. <em>The laws of physics are the same in all inertial systems. There is no preferential system.
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2. <em>The speed of light in vacuum has the same value for all inertial systems.
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Focusing on the first postulate, it can be affirmed that <u>any measurement on a body is made with reference to the system in which it is being measured</u>.
Now, taking into account that an inertial reference system is the one that complies with the principle of inertia:
<em>"For a body to have acceleration, an external force must act on it."</em>
The correct answer is
Within any frame of reference that is accelerating
It will take "Exact 75 years", 'cause light takes 1 year for 1 light years.
Hope this helps!
Electromagnetic because Light is an electromagnetic wave and can travel through the vacuum of outer space.
Answer:
Symbol N
Explanation:
The SI unit of force is the newton, symbol N