Forces acting on a two object system using free body diagram

AI Thread Summary
A force of 7.30 N pushes three boxes (m1=1.80kg, m2=3.00kg, m3=4.20kg) on a level surface, requiring a free body diagram (FBD) for boxes 2 and 3. The FBD must include the gravitational forces acting on both boxes, as well as the contact forces between the boxes and the floor. The correct identification of forces involves recognizing that gravity always acts downward on the boxes, while contact forces arise from their interactions. The user has attempted various combinations to represent the forces but has not found the correct solution. Understanding the roles of external and contact forces is crucial for accurately depicting the system.
meaganl
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Homework Statement


threeboxes.gif

A force of magnitude F= 7.30 N pushes three boxes with masses m1= 1.80kg, m2= 3.00kg and m3= 4.20kg, on a level surface.
Draw a free body diagram showing all the individual forces acting on the system consisting of boxes 2 and 3 together. Indicate the directions of the five forces listed below, choosing from vectors A-D in the diagram. If a force does not belong on the FBD, enter N.
directions.gif

i) gravity pulling on box 3
ii) gravity pulling on box 2
iii) box 1 pushing on box 3
iv) floor pushing on box 2
v)floor pushing on box 1

Homework Equations





The Attempt at a Solution



I have tried many solutions like NNNAN, CCNAN,CCNBN and more but it keeps telling that I'm wrong.
 
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