---
title: "A car is driving at 25m/s when a light turns red 100m ahead. The driver takes an unknown amount of time to react and hit the brakes, but manages to skid to a stop at the red light. If μs=0.9 and μk=0.65, what was the reaction time of the driver?"
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url: "https://nerd-notes.com/ubq/29529/"
date_modified: "2024-09-05T07:19:15+00:00"
---

# A car is driving at 25m/s when a light turns red 100m ahead. The driver takes an unknown amount of time to react and hit the brakes, but manages to skid to a stop at the red light. If μs=0.9 and μk=0.65, what was the reaction time of the driver?

A car is driving at \(25 \, \text{m/s}\) when a light turns red \(100 \, \text{m}\) ahead. The driver takes an unknown amount of time to react and hit the brakes, but manages to skid to a stop at the red light. If \(\mu_s = 0.9\) and \(\mu_k = 0.65\), what was the reaction time of the driver?

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/29529/*