What is the Average Velocity of a Motorist with Multiple Legs of Travel?

AI Thread Summary
The motorist drives for 35 minutes at 85 km/h, covering approximately 49.7 km, then takes a 15-minute break, and finally travels 130 km in 2 hours. The total displacement is calculated as 180 km. To find the average velocity, the total displacement is divided by the total time of 170 minutes, resulting in an average velocity of 1.06 km/m. The initial calculation was corrected after realizing an error in the average velocity computation. The discussion highlights the importance of accurately accounting for both distance and time in velocity calculations.
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Homework Statement


A motorist drives for 35 minutes at 85km/h and then stops for 15.0 minutes. He then continues traveling 130km in 2 hours. a) What is his total displacement? b) What is his average velocity?


Homework Equations


v= ∆X/∆t (Change in displacement over change in time)


The Attempt at a Solution


I divided 85/km/h and 60 minutes. That makes 1.42 km/m. I timed that by (35) minutes and for the first leg he traveled 49.7km. During the 15 minute break he traveled 0. During the second leg that distance was given (130km). So, 49.7km + 130km gives us the displacement of 180km (roughly).

Now I'm having a hard-time with the average velocity. I use to above formula and get 180km/170minutes (180km is the change in displacement and 170 minutes is the change in time (35m+15m+120m). The answer 1.06km/m seems a little weird to me.
 
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