---
title: "A \\( 12\\,600 \\) \\( \\text{kg} \\) railroad car travels alone on a level frictionless track with a constant speed of \\( 18.0 \\) \\( \\text{m/s} \\). A \\( 5350 \\) \\( \\text{kg} \\) load, initially at rest, is dropped onto the car. What will be the car’s new speed?"
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url: "https://nerd-notes.com/ubq/108185/"
date_modified: "2026-08-18T02:38:09+00:00"
---

# A \( 12\,600 \) \( \text{kg} \) railroad car travels alone on a level frictionless track with a constant speed of \( 18.0 \) \( \text{m/s} \). A \( 5350 \) \( \text{kg} \) load, initially at rest, is dropped onto the car. What will be the car’s new speed?

A \( 12\,600 \) \( \text{kg} \) railroad car travels alone on a level frictionless track with a constant speed of \( 18.0 \) \( \text{m/s} \). A \( 5350 \) \( \text{kg} \) load, initially at rest, is dropped onto the car. What will be the car’s new speed?

Figure 1. A railroad car moving on a track before and after a load is dropped onto it.

![Figure 1. A railroad car moving on a track before and after a load is dropped onto it.](https://nerd-notes.com/wp-content/uploads/ubq-diagrams/nerd-notes-physical-setup-108185-1773216558.png)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/108185/*