---
title: "A simple pendulum consists of a small bob of mass \\(m\\) attached to an ideal string of length \\(L\\). The bob is pulled to an angle \\(\\theta_0\\) from the vertical and released from rest at time \\(t = 0\\), undergoing simple harmonic motion in a vertical plane. Which of the following free-body diagrams best represents the forces acting on the bob at the instant it is released?"
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url: "https://nerd-notes.com/ubq/121032/"
date_modified: "2026-08-23T04:46:06+00:00"
---

# A simple pendulum consists of a small bob of mass \(m\) attached to an ideal string of length \(L\). The bob is pulled to an angle \(\theta_0\) from the vertical and released from rest at time \(t = 0\), undergoing simple harmonic motion in a vertical plane. Which of the following free-body diagrams best represents the forces acting on the bob at the instant it is released?

A simple pendulum consists of a small bob of mass \(m\) attached to an ideal string of length \(L\). The bob is pulled to an angle \(\theta_0\) from the vertical and released from rest at time \(t = 0\), undergoing simple harmonic motion in a vertical plane. Which of the following free-body diagrams best represents the forces acting on the bob at the instant it is released?

![A schematic diagram of a simple pendulum. At the top, a horizontal line represents a fixed support. A dashed vertical line drops downward from a pivot on the support. A straight solid line of length L extends from the pivot downward and to the right at an angle \theta_0 relative to the dashed line. At the lower end of the line is a small solid circle of mass m. A curved arc indicates the angle \theta_0 between the vertical dashed line and the string. No other labels, lines, text, or axes appear.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1787460365-M2z3M5.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/121032/*