So the initial velocity is 15 m/s, the final velocity is 0 since it's at a complete stop and time is 10 seconds. Therefore:

Therefore, the acceleration is -1.5 m/s^2. The reason it's negative is due to the fact that the vector is going against it's original movement since it's decelerating.
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.
Answer:
The gravitational force between them increases by a factor of 4
Explanation:
Gravitational force is a force of attraction between two objects with masses M and m which are separated by a distance R. It is given mathematically as:
Fg = GMm/R²
Where G = Gravitational constant.
If the distance between their centers, R, decreases by a factor of 2, then it means the new distance between their centers is:
r = R/2
Hence,the gravitational force becomes:
Fg = GMm/r²
Fg = GMm/(R/2)²
Fg = GMm/(R²/4)
Fg = 4GMm/R²
Hence,the gravitational force increases by a factor of 4.
Answer:
The volume of copper is 2.198 ml
Explanation:
Given;
mass of copper, m = 20 g
density of copper, ρ = 9.1 g/ml
Density is given by;
Density = mass / volume
Volume = mass / density
Volume = (20 g) / (9.1 g/ml)
Volume = 2.198 ml
Therefore, the volume of copper is 2.198 ml