---
title: "A block of mass \\(1.0\\text{ kg}\\) is attached to an ideal horizontal spring and undergoes simple harmonic motion on a frictionless surface. The total mechanical energy of the block-spring system is \\(18\\text{ J}\\). What is the instantaneous speed of the block at a position where the elastic potential energy of the spring is equal to \\(75\\%\\) of the total mechanical energy?"
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url: "https://nerd-notes.com/ubq/124563/"
date_modified: "2026-09-28T14:08:38+00:00"
---

# A block of mass \(1.0\text{ kg}\) is attached to an ideal horizontal spring and undergoes simple harmonic motion on a frictionless surface. The total mechanical energy of the block-spring system is \(18\text{ J}\). What is the instantaneous speed of the block at a position where the elastic potential energy of the spring is equal to \(75\%\) of the total mechanical energy?

A block of mass \(1.0\text{ kg}\) is attached to an ideal horizontal spring and undergoes simple harmonic motion on a frictionless surface. The total mechanical energy of the block-spring system is \(18\text{ J}\). What is the instantaneous speed of the block at a position where the elastic potential energy of the spring is equal to \(75\%\) of the total mechanical energy?

- **A.** \(1.5\text{ m/s}\)
- **B.** \(3.0\text{ m/s}\)
- **C.** \(5.2\text{ m/s}\)
- **D.** \(6.0\text{ m/s}\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/124563/*