Why does the mass of both objects not factor? Did I misunderstand the reason for differing gravity on other planets?
In: Physics
it’s a bit simpler if we look at these two formulas.
the gravitation formula is as follows: G * (m1 * m2) / (r^2)
G is a constant so we can ignore it. m1, m2 are the masses of the two objects that attract each other (earth and a ball for instance). r is just the distance between the objects.
if you look at this, we can see that it depends on the mass.
we can confirm this by taking into consideration the gravitational force of a black hole
and the formula for speed, taking into consideration the formula of speed, based on acceleration and original speed: s1 = s0 + a * t
we can see that this is not related to the mass (if we consider no friction with the air).
this goes beyond the ELI5 ideea but we can extract the speed of an object based on a basic mechanics calculation. knowing that energy is always conserved, we determine that the potential energy at a height (h) is equal to the kinetic enegy at the instant before hitting the ground
as such, we have: m * g * h = (m * v ^ 2) / 2
we can divide with the object’s mass (m) and we get: g * h = (v ^ 2) / 2
as we can see, an object’s speed, when reaching the ground is the same, regardless of its weight.
Latest Answers