Question

Can someone explain this force problem to me between 3 boxes? Will draw

Answer 1

A force of magnitude 7.5N pushes three boxes with masses m1=1.3 m2=3.2 m3=4.9 find the contact forces between boxes 1 and 2 and 2 and 3

Answer 2

I know the solution I just dont understand how to draw the forces

Answer 3

I dont get why its 7.5= a( m1+m2+m3)

Answer 4

why arent the forces like this to be more specific