Answer
moving the balls closer together
pumping more air into the soccer ball
putting the baseball in a plastic case
Explanation
Gravitational force is the force of attraction between two bodies of given masses. It is calculated by the formula;
Gravitational force = Gm₁m₂/r²
This formula shows that the force is directly proportional to G and the masses of the 2 bodies and inversely proportional to square of the distance between them.
∴ The following statements will cause a change in gravitational force;
moving the balls closer together ⇒ Increases the gravitational force
pumping more air into the soccer ball ⇒ Increases the mass of the ball hence increasing the gravitational force.
putting the baseball in a plastic case ⇒ It increases the mass of the ball hence increasing the gravitational force.
