I see the light moving exactly at speed equal to c.
In fact, the second postulate of special relativity states that:
"The speed of light in free space has the same value c<span> in all inertial frames of reference."
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The problem says that I am moving at speed 2/3 c, so my motion is a uniform motion (constant speed). This means I am in an inertial frame of reference, so the speed of light in this frame must be equal to c.
Answer:
C. nuclear fusion, because the equation shows two hydrogen nuclei combining to form a helium nucleus
Explanation:
Nuclear reaction can either be; fission or fusion. Nuclear fission is the process by which a massive nucleus breaks in to two smaller nuclei of almost the same size with the release of high amount of energy. Nuclear fusion is the process by which two nuclei reacts, joins, to produce a massive nucleus (compared to the masses of the reacting elements) with the release of high amount of energy.
From the given equation, two hydrogen isotopes; deuterium and tritium reacts with each other to produce helium nucleus and a neutron.
This reaction is a nuclear fusion which produces a massive nuclei.
Answer:
The centripetal force acting on the child is 39400.56 N.
Explanation:
Given:
Mass of the child is, 
Radius of the barrel is, 
Number of revolutions are, 
Time taken for 10 revolutions is, 
Therefore, the time period of the child is given as:

Now, angular velocity is related to time period as:

Now, centripetal force acting on the child is given as:

Therefore, the centripetal force acting on the child is 39400.56 N.
<span>When the particles of a medium move with simple harmonic motion, this means the wave is a sinusoidal wave.
Know that a sinusoidal curve can describe either sine or cosine functions (remember your cofunction identities for sine and cosine).</span>