---
title: "A sphere of mass \\(0.5\\) \\(\\text{kg}\\) is dropped into a column of oil. At the instant the sphere becomes completely submerged in the oil, the sphere is moving downward at \\(8\\) \\(\\text{m/s}\\), the buoyancy force on the sphere is \\(4.0\\) \\(\\text{N}\\), and the fluid frictional force is \\(4.0\\) \\(\\text{N}\\). Which of the following describes the motion of the sphere at this instant?"
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url: "https://nerd-notes.com/ubq/79351/"
date_modified: "2025-03-04T12:19:12+00:00"
---

# A sphere of mass \(0.5\) \(\text{kg}\) is dropped into a column of oil. At the instant the sphere becomes completely submerged in the oil, the sphere is moving downward at \(8\) \(\text{m/s}\), the buoyancy force on the sphere is \(4.0\) \(\text{N}\), and the fluid frictional force is \(4.0\) \(\text{N}\). Which of the following describes the motion of the sphere at this instant?

A sphere of mass \(0.5\) \(\text{kg}\) is dropped into a column of oil. At the instant the sphere becomes completely submerged in the oil, the sphere is moving downward at \(8\) \(\text{m/s}\), the buoyancy force on the sphere is \(4.0\) \(\text{N}\), and the fluid frictional force is \(4.0\) \(\text{N}\). Which of the following describes the motion of the sphere at this instant?

- **A.** The sphere’s speed is decreasing while the sphere continues to move downward.
- **B.** The sphere is moving downward at a constant speed.
- **C.** The sphere’s speed is increasing while the sphere continues to move downward.
- **D.** The sphere’s speed is increasing as the sphere begins moving upward.

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/79351/*