Three blocks are in contact with each other on a frictionless horizont

[SaviLovesTW]

Homework Statement

Three blocks are in contact with each other
on a frictionless horizontal surface. A 503 N
horizontal force is applied to the block with
mass of 2.6 kg as shown in the figure below.
The acceleration of gravity is 9.8 m/s^2.

What is the magnitude of the force between
the block with mass 5.8 kg and 8.3 kg?

Homework Equations

The Attempt at a Solution

I understood the other parts but i can't figure out this question.

 

[berkeman]

Homework Statement

Three blocks are in contact with each other
on a frictionless horizontal surface. A 503 N
horizontal force is applied to the block with
mass of 2.6 kg as shown in the figure below.
The acceleration of gravity is 9.8 m/s^2.

What is the magnitude of the force between
the block with mass 5.8 kg and 8.3 kg?

Homework Equations

The Attempt at a Solution

I understood the other parts but i can't figure out this question.

Welcome to the PF.

With questions like this, start by drawing a free body diagram (FBD) for each mass in the question. Label each FBD with all of the forces acting on the body.