Know that the strength of the gravitational field (a) at the surface of a planet depends on the mass of the planet (b) around a planet decreases as the distance from the planet increases

State that the acceleration of free fall g for an object near to the surface of the Earth is approximately constant and is approximately 9.8 m/s²

Define gravitational field strength as force per unit mass; recall and use the equation g = W/m and know that this is equivalent to the acceleration of free fall