Question

Four 7.0 kg spheres are located at the corners of a square o

Answer 1

See theFig

magnitude of F1=G*m*m/r^2

magnitude of F2=G*m*m/r^2

magnitude of F3=G*m*m/(2*r^2)

magnitude of of the gravitational force on one sphere due to the other three F=2^(1/2)*G*m*m/r^2+(1/2)*G*m*m/r^2

G=6.67×10^(-11) N·m2 /kg2

so magnitude of F=[2^(1/2)+1/2]*6.67×10^(-11)*7*7/(0.52*0.52)=2.313*10^(-8)

direction of the gravitational force towards the sphere at the catercorner(对角线)