Calculating Contact Forces Between Blocks on a Frictionless Surface

AI Thread Summary
The problem involves calculating the contact forces between three blocks on a frictionless surface when a horizontal force is applied to the first block. The user attempted to use a formula to find the contact forces between blocks 1 and 2, and blocks 2 and 3, but their calculations yielded incorrect results. The user specifically used the formula P=(M2/(M1+M2)) x F for block 1 and P=(M3/(M2+M3)) x F for block 2. The discussion seeks clarification on the correct approach to determine the contact forces. Accurate calculations are essential for understanding the dynamics of the system.
Lannie
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This problem seemed very straightforward but I've somehow missed something...

Three blocks (M1, M2, M3) are in contact with each other on a frictionless, horizontal surface. A horizontal force is applied to M1.

If M1= 1.67kg, M2= 2.67kg, M3= 3.78kg, and F= 16.1 N:

a) what is the magnitude of the contact force between blocks 1 and 2
b) what is the magnitude of the contact force between blocks 2 and 3


I used the formula P=(M2/M1+M2) x F to find these contact forces, but the answers I got were not correct.

for a) I calculated P= (2.67/1.67+2.67) x 16.1
and for b) I calculated P= (3.78/2.67+3.78) x 16.1

This seemed like it should lead to the right answer, but it didn't work. Anyone know what I've done wrong?
 
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that makes sense :) thanks for the help
 
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