## Engineering Mechanics: Statics & Dynamics (14th Edition)

$F=10.0\mu N$ $W_1=78.5 N$ $W_2 =118 N$
We are given that two particles have a mass of 8 kg and 12 kg, respectively and that they are 800 mm apart. We are asked to determine the force of gravity acting between them. We will use equation 1-2 $F=G *\frac{m_1*m_2}{r}$ $F=66.73m^3/(kg *s^2)*\frac{8kg*12kg}{0.800m}$ $F=10.0 *10^{-9}N$ or $10.0\mu N$ Now we will compare that to the weight of each particle. $W_1 = 8kg(9.81m/s^2) = 78.5 N$ $W_2 = 12kg(9.81m/s^2) = 118 N$ We can see that the force of gravity acting between them is very small compared to the weight of each particle.