---
title: "A person is standing at the edge of the water and looking out at the ocean. The height of the person’s eyes above the water is \\( h = 1.8 \\, \\text{m} \\), and the radius of the Earth is \\( R = 6.38 \\times 10^6 \\, \\text{m} \\). How far is it to the horizon (in meters)? In other words, find the distance \\( d \\) from the person’s eyes to the horizon.  (Note: At the horizon, the angle between the line of sight and the radius of the Earth is \\( 90^\\circ \\).)"
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url: "https://nerd-notes.com/ubq/19540/"
date_modified: "2025-08-22T10:28:46+00:00"
---

# A person is standing at the edge of the water and looking out at the ocean. The height of the person’s eyes above the water is \( h = 1.8 \, \text{m} \), and the radius of the Earth is \( R = 6.38 \times 10^6 \, \text{m} \). How far is it to the horizon (in meters)? In other words, find the distance \( d \) from the person’s eyes to the horizon.  (Note: At the horizon, the angle between the line of sight and the radius of the Earth is \( 90^\circ \).)

A person is standing at the edge of the water and looking out at the ocean. The height of the person’s eyes above the water is \( h = 1.8 \, \text{m} \), and the radius of the Earth is \( R = 6.38 \times 10^6 \, \text{m} \). How far is it to the horizon (in meters)? In other words, find the distance \( d \) from the person’s eyes to the horizon. Note at the horizon, the angle between the line of sight and the radius of the Earth is \( 90^\circ \).)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/19540/*