Multiple-Object Systems with Friction: Block a of Mass 5

question 118

Multiple Choice

Multiple-object systems with friction: Block A of mass 5.0 kg and block X are attached to a rope which passes over a pulley, as shown in the figure. An 80-N force P is applied horizontally to block A, keeping it in contact with a rough vertical face. The coefficients of static and kinetic friction between the wall and block A are μ_s = 0.40 and μ_k = 0.30. The pulley is light and frictionless. The mass of block X is adjusted until block A moves upward with an acceleration of 1.6 m/s². What is the mass of block X?

• A) 9.9 kg
• B) 9.3 kg
• C) 8.7 kg
• D) 8.1 kg
• E) 7.5 kg

---

Definitions:

Unstable Relationships

Interpersonal connections characterized by unpredictability, intense emotions, and frequent conflicts or changes in feelings.

Borderline Personality Disorder

a mental illness characterized by pervasive instability in moods, self-image, and behavior, often leading to impulsive actions and unstable relationships.

Manic Behavior

A state of heightened energy, mood, and activity levels, often seen in bipolar disorder during the manic phase.

DSM-5

The Fifth Edition of the Diagnostic and Statistical Manual of Mental Disorders, an extensive categorization of formally acknowledged psychiatric conditions, released by the American Psychiatric Association.