k{g^{- 2}}\). Overall this equation is simpler than it looks as long as you ensure that: distance is given between centres units are all in metres and kilograms The force of gravity exists between ...

Gravitational forces that make things fall down to the ground – unless another force stops them. An apple falling from a tree falls straight down. A ball thrown up, comes back down. And so do we ...

In 2018, scientists redefined the kilogram related to the basic electromagnetic principles ... units could now be defined in terms of gravitational force instead of just an electrical one.