Two boxes of 15.0 kg are measure to be 0.85 m apart from center to center. What is the attractive gravitational force that exists between the two boxes?

Question

Two boxes of 15.0 kg are measure to be 0.85 m apart from center to center.  What is the attractive gravitational force that exists between the two boxes?

jfraser · Answer

plug into the formula for universal gravitation. This is also physics, and better belongs in that group.$$F_G = \frac{G*M_1*M_2}{r^2}$$

anonymous · Answer

okay I am not sure which numbers to put into the parts of the equation.  What does g and m represent?

jfraser · Answer

"G" is the universal gravitation constant, easy to look up. M1 and M2 are the masses of the objects

anonymous · Answer

okay! Awesome I think I can figure it out now.

anonymous · Answer

6.67*10^-11 is the universal gravitation.

jfraser · Answer

yes

anonymous · Answer

I keep getting 2.07 but I don't think that is right

anonymous · Answer

2.07*10^-8 N

jfraser · Answer

why not?

anonymous · Answer

Because I have 3 answers to choose from and that is not one of them.  I thought that i got it right though.

anonymous · Answer

The closest one is 2.1*10^-8 N

jfraser · Answer

what's the real difference between 2.10 and 2.07?

anonymous · Answer

I guess it is not very much.  So it will be 2.10.

jfraser · Answer

2.10*10-8N, don't forget the exponents

anonymous · Answer

Right.  :)  Thanks!