A 55.0 kg student feels a 2.68x10^-8 N gravitational force from a physics book 0.435 m away. what is the mass of the physics book?
F =[ G. M * m] / r^2
2.68E-8 =[6.67428E-11 * 55 * m] / .435^2, solve for m.
2.68×10^-8 = 1.93994×10^-8 m
Divide both sides by 1.93994E-8
m = 1.38149 - Kg - mass of the Physics' Book.