---
title: "A hypothetical planet is observed to have an initial mass M and an initial radius R, resulting in a gravitational field strength of g_0 at its surface. Due to a unique geological event, the planet contracts such that its radius becomes R/2 while its total mass M remains unchanged. What is the new gravitational field strength at the surface of the planet?"
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url: "https://nerd-notes.com/ubq/109928/"
date_modified: "2026-03-26T06:56:42+00:00"
---

# A hypothetical planet is observed to have an initial mass M and an initial radius R, resulting in a gravitational field strength of g_0 at its surface. Due to a unique geological event, the planet contracts such that its radius becomes R/2 while its total mass M remains unchanged. What is the new gravitational field strength at the surface of the planet?

A hypothetical planet is observed to have an initial mass M and an initial radius R, resulting in a gravitational field strength of g_0 at its surface. Due to a unique geological event, the planet contracts such that its radius becomes R/2 while its total mass M remains unchanged. What is the new gravitational field strength at the surface of the planet?

![A diagram showing two spheres. The first sphere is labeled Initial State with radius R and mass M. The second sphere is smaller, labeled Final State with radius R/2 and mass M. Arrows point toward the center of each sphere from the surface, labeled g_0 and g_new respectively.](https://nerd-notes.com/wp-content/uploads/ubq-frq-generated/stem-fig-1-1774508201-iYtRXI.jpg)

- **A.** \(g_0 / 4\)
- **B.** \(g_0 / 2\)
- **C.** \(2g_0\)
- **D.** \(4g_0\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/109928/*