How Do You Incorporate Drag Force in Free Body Diagrams for Multiple Objects?

AI Thread Summary
To incorporate drag force in free body diagrams for multiple objects, it is essential to start by drawing a separate free body diagram for each object, in this case, the ducks. Assign unknown forces consistently between the objects, particularly focusing on the drag force exerted by duck 3 on the first two ducks. After establishing the diagrams, apply Newton's second law (F=ma) to each duck, ensuring that all forces, including drag, are accounted for in the equations. This method allows for a systematic approach to analyze the interactions and forces at play. Understanding these steps is crucial for accurately modeling the dynamics of the system.
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Homework Statement
Three toy ducks on wheels are attached to the same rope and a boy begins pulling one end of the rope with a force of 10 N. The first duck (duck 1) has a mass of 1.0 kg, the middle duck (duck 2) has a mass of 5.0 kg, and the third duck in line (duck 3) has a mass of 2.0 kg. I already calculated the acceleration of the three ducks in part a of this question (1.25 m/s^2). The next thing is to find the tension force in the rope connecting ducks 1 and 2. I don't understand how to go about doing this: any help is appreciated!
Relevant Equations
F = ma
I don't even know how to begin this. I know that I need to somehow account for the drag force that duck 3 is causing on the first 2, but I don't know how to deal with that. I am asking for someone to help me get started, not to give me the answer.
 
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There can be shortcuts, but the standard procedure is to draw a free body diagram for each duck and assign unknowns to the forces between them in a consistent manner.
Then write the F=ma equation for each duck.
 
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