How is Average Speed Calculated for a Two-Part Journey?

Thread starter chawki
Start date Mar 15, 2011
Tags

Average Average speed Car Speed

AI Thread Summary

To calculate the average speed for a two-part journey, the total distance and total time must be considered. In this case, a car travels 19 km at 91 km/h and 61 km at 65 km/h. The time for the first segment is approximately 0.208 hours, and for the second segment, it is about 0.938 hours. The overall average speed is calculated by dividing the total distance (80 km) by the total time (1.146 hours), resulting in an average speed of approximately 69.81 km/h. This method effectively determines the average speed for multi-segment journeys.

Mar 15, 2011

chawki

Homework Statement

A car is driven 19 km at an average speed of 91 km/h and after that 61 km at an
average speed of 65 km/h.

Homework Equations

What was the average speed of the whoIe joumey?

The Attempt at a Solution

t1=19/91 = 0.208 h
t2=61/65 = 0.938 h

average speed = (19+61)/(0.208+0.938)
average speed = 69.808 km/h

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Mar 15, 2011

SammyS

Staff Emeritus

Science Advisor

Homework Helper

This looks fine.

Mar 15, 2011

tiny-tim

Science Advisor

Homework Helper

looks ok!

Mar 16, 2011

ashishsinghal

its correct!

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