Question

The speed limit on some interstate highways is roughly 100 km/h. (a) What is this in meters per second? (b) How many miles per hour is this?

Question by OpenStax is licensed under CC BY 4.0.

a) $27.79 \textrm{ m/s}$

b) $62.1 \textrm{ mph}$

Solution Video

OpenStax College Physics Solution, Chapter 1, Problem 1 (Problems & Exercises) (2:11)

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Comments

Submitted by bam0072@auburn.edu on Wed, 09/22/2021 - 09:24

How did you get .621?

Submitted by ShaunDychko on Fri, 09/24/2021 - 12:13

Hi bam, thank you for the question. That might have been a Google search, or maybe I took the reciprocal of the conversion from miles to kilometers provided in the textbook. In any case, we want to know how many miles are in how many kilometers in order to create a fraction with miles on the top, and kilometers on the bottom. Writing the fraction as $\dfrac{1 \textrm{ mile}}{1.609 \textrm{ km}}$ would also work - test it out to confirm!
All the best,
Shaun

OpenStax College Physics Solution, Chapter 1, Problem 1 (Problems & Exercises) (2:11)

Calculator Screenshots

Comments

Solutions for problems in chapter 1