Finding the Acceleration of masses on a pulley

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SUMMARY

The discussion focuses on calculating the acceleration of two connected masses, M and m, on a pulley system. It establishes that both masses experience the same magnitude of acceleration due to their connection via massless, inextensible strings. The conversation also explores conditions under which mass M can ascend while mass m descends, emphasizing the importance of equilibrium in analyzing the forces acting on the masses. The fundamental equation used is the sum of forces equals mass times acceleration (F=ma).

PREREQUISITES
  • Understanding of Newton's Second Law (F=ma)
  • Basic knowledge of pulley systems and tension in strings
  • Concept of equilibrium in physics
  • Ability to analyze connected systems of masses
NEXT STEPS
  • Study the dynamics of pulley systems with multiple masses
  • Learn about tension forces in connected mass systems
  • Explore equilibrium conditions in mechanical systems
  • Investigate the effects of varying mass ratios on acceleration
USEFUL FOR

Students studying physics, particularly those focusing on mechanics and dynamics, as well as educators looking for examples of pulley systems in action.

rodrale25

Homework Statement


Masses M and m are connected to a system of strings and pulleys as shown
in the diagram below. The strings are massless and inextensible, and the p
ulleys are massless and
frictionless.
A: Find the accelerations for M and m (Hint: Think about these two questions:
Do these two masses have the same accelerations
in magnitude ? How is the distance that the lower pulley moves related to the distances
that masses M and m travels?)

B: One can imagine that when M is much larger than m, mass M would descend while mass m w goes up. Under what condition for M and m, would mass M go up while mass m descend? Explain your reasoning by considering the static situation (i.e., when the two masses are in equilibrium with neither M nor m moving)

Homework Equations


Sum of Forces=ma[/B]

The Attempt at a Solution


I said F= the sum of forces for just one of the masses and solved for a. Doing this for both masses, I got two separate accelerations, and then I realized that the two masses are connected. I know this isn't right because the two masses are connected by the strings somehow but I can't conceptually picture this.[/B]
 

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Hello Rod, :welcome:
rodrale25 said:
I know this isn't right because the two masses are connected by the strings somehow but I can't conceptually picture this
For this reason you are given hints in the form of two questions. What are your answers?
You get a third one from me :smile: : can you imagine an equilibrium situation ? If so, under what condition ?
[edit] reading ahead can be profitable (for folks like me too :rolleyes:): the same question is asked in part B.
 

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