If it were possible for an object to fall freely near the surface of the Earth,
-- The direction of its velocity would always be "down"; that is, toward the center of the Earth.
-- The size of its velocity would continually increase, at the rate of 9.8 meters per second for every second it falls.
Answer:
Explanation:
Let assume begins movement at zero point, that is, height is equal to zero. The block has an initial linear kinetic energy and no gravitational potential energy and end with no linear kinetic energy, some gravitational potential energy and work losses due to slide friction. In mathematical terms, this system can be model as follows:

Where
are linear kinetic energy, gravitational potential energy and work, respectively.
Answer:
4.2 x 10⁷N
Explanation:
Given parameters:
Charge on ball:
q₁ = 3C
q₂ = 14C
Distance between balls = 9000m
Unknown:
Force acting on the two balls
Solution:
The force experienced by the two charges is given by coulombs law. It is mathematically expressed as;
F = 
where k = 9 x 10⁹Nm²/C²
q is the charges
r is the distance
Input the variables and solve;
F =
= 4.2 x 10⁷N