Distance traveled using velocity

AI Thread Summary
The discussion centers on calculating the distance a dog travels while its two owners walk toward each other. The owners start 10 meters apart, each walking at 1.3 m/s, which means they will meet in 6.5 seconds. The dog runs back and forth at 3.0 m/s during this time, leading to a calculated distance of 19.5 meters. However, the correct answer is 11 meters, prompting confusion about the calculations. Simplifying the problem by treating one owner as stationary can help clarify the solution.
destinc
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1. A dog runs back and forth between its two owners, who are walking toward one another. The dog starts running when the owners are 10.0m apart. If the dog runs with a speed of 3.0m/s, and the owners each walk with a speed of 1.3m/s , how far has the dog traveled when the owners meet?


My attempt:
I know each owner will travel a distance of 5m at 1.3m/s which equals 6.5s of time. The dog travels 3.0m/s for the 6.5s= 19.5m traveled, but the answer given is 11m. What am I doing wrong?
 
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destinc said:
I know each owner will travel a distance of 5m at 1.3m/s which equals 6.5s of time.
How far do you travel in 6.5 sec if you go at 1.3 m/sec?
 
destinc said:
1. A dog runs back and forth between its two owners, who are walking toward one another. The dog starts running when the owners are 10.0m apart. If the dog runs with a speed of 3.0m/s, and the owners each walk with a speed of 1.3m/s , how far has the dog traveled when the owners meet?My attempt:
I know each owner will travel a distance of 5m at 1.3m/s which equals 6.5s of time. The dog travels 3.0m/s for the 6.5s= 19.5m traveled, but the answer given is 11m. What am I doing wrong?

Hey physics problems can be tough to get thru sometimes.

You can use an equation that relates velocity, time, and distance to get your answer.

Remember, Average velocity = Δx divided by Δt...where x is displacement and t is time. The trick here is also that you have two people moving at the same velocity closing a distance of 10m.

Once you have the time it takes for these two people to meet, solve for the Δx of the dog.
 
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destinc said:
My attempt:
I know each owner will travel a distance of 5m at 1.3m/s which equals 6.5s of time.✗[/size][/color]
...
 
You can also simplify the problem by treating one owner as being stationary and the other moving at 2.6m/s

EDIT: I got 11.5385, which I think you should round up...not quite sure about this method
 
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