In the image below, which objects would have a greater gravitational force between them, Objects A and B, or Objects B and C? Give one supporting detail for your answer. Three circles labeled Object A, Object B, and Object C. A is on the left, B is in the center and C is on the right. A and C are each the same distance away from B. A has a mass of 10 kg, B has a mass of 30 kg, and C has a mass of 30 kg.
Answers
Let’s examine this formula a bit more closely.
F refers to the gravitational force, the vector we ultimately want to compute and pass into our applyForce() function.
G is the universal gravitational constant, which in our world equals 6.67428 x 10^-11 meters cubed per kilogram per second squared. This is a pretty important number if your name is Isaac Newton or Albert Einstein. It’s not an important number if you are a ProcessingJS programmer. Again, it’s a constant that we can use to make the forces in our world weaker or stronger. Just making it equal to one and ignoring it isn’t such a terrible choice either.
m_1m
1
m, start subscript, 1, end subscript and m_2m
2
m, start subscript, 2, end subscript are the masses of objects 1 and 2. As we saw with Newton’s second law (\vec{F} = M\vec{A}
F
=M
A
F, with, vector, on top, equals, M, A, with, vector, on top), mass is also something we could choose to ignore. After all, shapes drawn on the screen don’t actually have a physical mass. However, if we keep these values, we can create more interesting simulations in which “bigger” objects exert a stronger gravitational force than smaller ones.
\hat{r}
r
^
r, with, hat, on top refers to the unit vector pointing from object 1 to object 2. As we’ll see in a moment, we can compute this direction vector by subtracting the location of one object from the other.