Alright, let's put on our nerd glasses for this one.
The force of gravity between two objects is governed by the equation known as Newton's law of universal gravitation. This law states:
F = G * (m1*m2) / r^2
where:
- F is the force between the two objects,
- G is the gravitational constant,
- m1 and m2 are the masses of the two objects, and
- r is the distance between the centers of the two objects.
Now, you've said one mass is doubled and the other is tripled. Let's call the initial mass of the planet 'm1' and the initial mass of the moon 'm2'. After the changes, the new mass of the planet becomes '2m1' and the new mass of the moon becomes '3m2'.
Substituting these into the equation, we get:
F' = G * ((2m1)*(3m2)) / r^2
=> F' = 6 * G * (m1*m2) / r^2
The initial gravitational force, F, is given by F = G * (m1*m2) / r^2. Therefore, the new gravitational force, F', is 6 times the original gravitational force, F.
So, to answer your multiple-choice question, the new gravitational force is 6F. Break out the victory dance, because physics just did us a solid!