David W. answered • 07/07/15
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It's not WyzAnt, but there's a good description of the difference between speed and velocity at--
http://www.differencebetween.com/difference-between-speed-and-vs-velocity/
David W.
The article states
"It is easy to find the distance traveled by a ball that has been thrown up in air and comes down to the same point. But the displacement of the ball is zero as it comes back to its start point."
and
"The same concept applies to speed and velocity. Where as speed is a scalar quantity that only tells you how fast an object is moving, velocity also tells you the direction of the moving body"
So, in the problem statement, both speed and velocity have units of miles per hour. However, velocity has a "+" of "-" to indicate direction (like a vector), but speed is just miles/hr.
For (b) the average speed is just (80 miles / 1.75 hr) = 45.7 mph.
For (a) the train returns to its starting position, so the average velocity is 0.
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07/07/15
Rebecca S.
Thank you so much again. So would the meters per second be 20.43?
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07/08/15
Andrew M.
Rebecca, I did the conversion form miles/hr to meters/sec and got the same answer of 20.43 m/sec
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07/08/15
Rebecca S.
Ok Thank you so much Andrew and David. I appreciate it greatly.
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07/08/15
David W.
My e-mail just beeped --- THX Andrew, I agree !
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07/08/15
Jessica B.
How did you guys convert it to mps? I’m having some difficulty doing it
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05/14/21
Rebecca S.
07/07/15