Three Boxes Are Pushed Across a Frictionless Horizontal Surface as Shown

Multiple Choice

Three boxes are pushed across a frictionless horizontal surface as shown. When we compare the normal force N2,5 that mass 2m exerts on mass 5m with the normal force N5,10 that mass 5m exerts on mass 10m, we find that:

A) N2,5 = N5,10 = F.
B) N2,5 = F > N5,10.
C) F > N2,5 = N5,10.
D) F > N2,5 > N5,10.
E) F > N5,10 > N2,5.