Two Masses and the Tension in a rod

AI Thread Summary
The discussion focuses on calculating the tension in a rod connecting two masses sliding down an inclined plane. The masses, m1 and m2, experience different coefficients of kinetic friction, affecting the forces acting on them. The calculations show that the tension for m1 is 5.02N and for m2 is 13.27N, leading to a total tension of 8.25N in the rod. Participants emphasize the importance of using free body diagrams to analyze the forces and clarify that the tension in the rod is the same for both masses, just in opposite directions. The thread seeks verification of the calculations and understanding of the tension dynamics involved.
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Homework Statement



Two masses, m1 = 1.65kg and m2 = 3.30kg, attached by a massless rod parallel to the inclined plane on which they both slide, travel along the plane with m1 trailing m2. The angle of incline is 30°. The coefficient of kinetic friction between m1 and the incline is μ1 = 0.226; that between m2 and the incline is μ2 = 0.113.

What is the tension in the rod?

Homework Equations



Ff = μk × FN

FN = mgcosθ

The Attempt at a Solution



So, for m1:

Ff1 = μ1 × FN
Ff1 = 0.226 × mgcos30
Ff1 = 0.226 × 14.29
Ff1 = 3.23N

Force Down Incline = mgsin30
Force Down Incline = 8.25N

Therefore, Tension 1 = Force Down Incline - Ff1 = 5.02N

And for m2:

Ff1 = μ1 × FN
Ff1 = 0.113 × mgcos30
Ff1 = 0.226 × 28.58
Ff1 = 3.23N

Force Down Incline = mgsin30
Force Down Incline = 16.5N

Therefore, Tension 2 = Force Down Incline - Ff2 = 13.27NFinally, Total Tension = Tension 2 - Tension 1 = 8.25N

There are no answers for this question, so I came on here hoping that someone may be able to correct me if I have done something wrong, or possibly verify my answer.

Any help greatly appreciated!

Thanks :)
 
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What is the tension in the rod?
Tension 1= Tensiion 2
 
azizlwl said:
What is the tension in the rod?
Tension 1= Tensiion 2

What do you mean sorry?
 
If you hang an object of mass m by a massless rod , what is the tension on the rod?
 
azizlwl said:
If you hang an object of mass m by a massless rod , what is the tension on the rod?

That is my question haha.
 
The upper mass will pull up the lower mass.
The reaction of this the lower will pull the upper mass too.
So action and reaction are the same tension on the rod.
Use fbd for the lower mass and the upper mass to find the tension where tension pull are the same, only different direction.
 
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