This might help and it might not:
Gravitation is the acting force between two bodies. On the other hand, gravity is the force occurring between an object and the very big object earth. Every object with some mass exerts the gravitational force on every other object having some mass. This force and its strength depend on the masses of the objects under consideration. Gravity helps to keep the planets to move in their orbit around the sun.
Gravitation is the force of attraction between any two bodies in the universe. In our universe, each object attracts each other with a certain amount of force. The large distance of separation is the main reason for its weak nature.
Gravity is the weakest type of fundamental force in nature. Still, it holds together the entire solar systems and galaxies.
Gravity has the existence with unlimited range.
High density
random words to fill up 20 character minimum for answering questions :P
Answer:
W = 9.93 10² N
Explanation:
To solve this exercise we must use the concept of density
ρ = m / V
the tabulated density of copper is rho = 8966 kg / m³
let's find the volume of the cylindrical tube
V = A L
V = π (R_ext ² - R_int ²) L
let's calculate
V = π (4² - 2²) 10⁻⁴ 3
V = 1.13 10⁻² m³
m = ρ V
m = 8966 1.13 10⁻²
m = 1.01 10² kg
the weight of the tube
W = mg
W = 1.01 10² 9.8
W = 9.93 10² N
They have the same velocity because their displacements (shortest line from point A to point B, which is a straight line) are the same and they meet at the same time.
Harnessing the sun's energy to produce heat or electricity is : A. Non - Polluting
This energy generating method will cause no dangerous emission for environment (unlike the one that came from fossil fuel), but the energy that produced from the sun tend to be more expensive so it's still not widely used
hope this helps