Posted by Stanley on .
A chain composed of four identical links is suspended by a rope and does not move. How many force vectors would be drawn on the free body diagram of each link and which direction would they point?
My answer:

FIRST LINK (top): Upward force from rope (tension), downward normal force from link 2 (below), and downward force from earth (weight)
SECOND LINK: Upward normal force from link 1 (above), downward normal force from link 3 (below), and downward force from earth (weight)
THIRD LINK: Upward normal force from link 2 (above), downward normal force from link 4 (below), and downward force from earth (weight)
FOURTH LINK (bottom): Upward normal force from link 3 (above), downward force from earth (weight)

Magnitudes from largest to smallest:
Upward force from rope
Downward normal force on link 1 from link 2=Upward normal force on link 2 from link 1
Downward normal force on link 2 from link 3=Upward normal force on link 3 from link 2
Downward normal force on link 3 from link 4=Upward normal force on link 4 from link 3 = W4 = W3 = W2 = W1
(Where W4 = Weight of link 4, W3 = Weight of link 3, W2 = Weight of link 2, and W1= Weight of link 1, all of which are equivalent)

^ Is all of that right?

Physics 
bobpursley,
I don't understand you writing, but the force pulling downward on the first link is the weight of three links.The force pulling up is tension= weight of four links.