Answer:
Density is the relationship between mass and volume.
D = M / V
Explanation:
Definition of electromagnetic wave. : one of the waves that are propagated by simultaneous periodic variations of electric and magnetic field intensity and that include radio waves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
Answer: C. good reflector of heat
Explanation:
In space, sunlight transfers heat by radiation to objects and bodies and this includes satellites and astronauts. In addition, although the peak of the sun's emission is in the visible region of the electromagnetic spectrum, a part is also emitted in infrared (transferring thermal energy or heat) and ultraviolet (especially in the upper part of the Earth's atmosphere).
That is why in space missions, objects and many satellites are covered by thin layers or sheets that reflect this thermal energy and thus avoid damaging the equipment due to high temperatures.
In this sense, among the reflective materials used are aluminum, silver, copper and gold; the latter being the most used because it does not corrode or oxidize (unlike silver and copper) and is more malleable than aluminum.
On the other hand, <u>astronauts are also vulnerable to the effects of infrared radiation, especially their eyes</u>, since the human eye has no receptors in the infrared spectrum. <u>That is why the astronaut's helmet visor is covered with a thin layer of gold to avoid the dangerous effects of solar radiation.</u>
To solve the problem, it is necessary to use the concepts of gravitational force, centripetal force and trigonometric components that can be extrapolated from the statement.
By definition we know that the Force of Gravity is given by
Where,
m= Mass
g = Gravitational Acceleration
The centripetal force is given by,
Where,
m = Mass
v = Velocity
R = Radius
For the case described in the problem, the Force of gravity the net component would be given by sin?, While for the centripetal force the net component is in the horizontal direction, therefore it corresponds to the 
Then,
From the radius we have its length but not the net height, which would be given by
So equating the equations we have to
Re-arrange to find v,
Replacing with our values
Therefore the tangential velocity of the mass is 0.624m/s
