Fictitious force in a binary stars

Thread starter Rikudo
Start date Aug 23, 2022
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Binary Fictitious force Force Stars

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Fictitious forces arise in non-inertial frames of reference, complicating the understanding of motion in binary star systems. The discussion emphasizes the need to clarify which frame of reference is being considered to address the question effectively. It suggests focusing on the frame of reference of mass 'm' to determine the fictitious force that, when combined with the normal force, yields the instantaneous acceleration of 'm'. Understanding these forces is crucial for accurately analyzing dynamics in such systems. Clarity in the frame of reference is essential for resolving the complexities of fictitious forces in binary stars.

Aug 23, 2022

Rikudo

Homework Statement: Two planets with mass M1 and M2 revolve around each other in circular orbits. The distance between them is r. A mass m that is located on the surface of M1 with radius R feels fictitious force that modifies the mass's acceleration. Assume that mass m is very small and ignore the effect from M1's rotation. (see figure)

Write down the vector of the fictitious force in m, M2, r, gravity constant G, and unit vector!

Relevant Equations: -

I have a difficulty in understanding the question.
Fictitious force is a force whose motion is described using a non-inertial frame of reference. Which frame is the question referring to?

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Aug 24, 2022

haruspex

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Rikudo said:

Which frame is the question referring to?

Excellent question!
I suggest m's frame of reference, i.e. find that force which, added to the normal force, results in m's instantaneous acceleration.

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