---
title: "A block of mass \\(M_1\\) is placed on a rough horizontal table and connected by an ideal string over a frictionless pulley to a hanging block of mass \\(M_2\\), as shown in the diagram. After the system is released from rest, the blocks accelerate. The coefficient of kinetic friction between block 1 and the table is \\(\\mu_k\\). Which of the following sets of free-body diagrams correctly represents the forces acting on each block while they are in motion?"
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url: "https://nerd-notes.com/ubq/112657/"
date_modified: "2026-05-01T04:41:23+00:00"
---

# A block of mass \(M_1\) is placed on a rough horizontal table and connected by an ideal string over a frictionless pulley to a hanging block of mass \(M_2\), as shown in the diagram. After the system is released from rest, the blocks accelerate. The coefficient of kinetic friction between block 1 and the table is \(\mu_k\). Which of the following sets of free-body diagrams correctly represents the forces acting on each block while they are in motion?

A block of mass \(M_1\) is placed on a rough horizontal table and connected by an ideal string over a frictionless pulley to a hanging block of mass \(M_2\), as shown in the diagram. After the system is released from rest, the blocks accelerate. The coefficient of kinetic friction between block 1 and the table is \(\mu_k\). Which of the following sets of free-body diagrams correctly represents the forces acting on each block while they are in motion?

![A block M1 sits on a horizontal surface. A string attached to the right side of M1 passes over a pulley at the edge of the table and connects to a hanging block M2. M1 is labeled with mass M1 and M2 is labeled with mass M2.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1777511946-p8BSTY.jpg)

- **A.** Diagram A
- **B.** Diagram B
- **C.** Diagram C
- **D.** Diagram D

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/112657/*