Answer:
a. Light pollution refers to light used for human activities that brightens the sky and hinders astronomical observations.
Explanation:
Light pollution is due to the excessive and misdirected use of artificial light. Light bulbs are often design in an incorrect way, since a great part of its light is not completely directed to the ground and an important percentage is emitted to the sky in where will be scattered and reflected back to ground by the particles in the atmosphere. That brings as an effect a sky glow, therefore the visibility of astronomical objects will be extremely reduce.
Hence, professional astronomical research and amateur observations will be affected. Light pollution has a negative impact on bird migration at night and in the health of difference species, humans also.
The answer would be D, electromagnetic waves
A spring that obeys Hooke's law has a spring force constant of 272 N/m. This spring is then stretched by 28.6 cm
Answer:
0.4 g/cm^3
Explanation:
The density of an object can be found using the following formula.
d= m/v
where m is the mass and v is the volume.
The mass of the metal is 6 grams and the volume is 15 centimeters^3
m=6 g
v= 15 cm^3
Substitute these into the formula.
d= 6 g/ 15 cm^3
Divide 6 g by 15 cm^3 (6/15=0.4)
d= 0.4 g/ cm^3
The density of the metal is 0.4 grams per cubic centimeter.