Vectors - velocity is changing but speed is not

AI Thread Summary
The discussion focuses on identifying a pair of vectors that illustrate a scenario where an object's velocity changes while its speed remains constant. Participants analyze various options, debating the implications of acceleration on speed and direction. It is noted that if acceleration is in the opposite direction of velocity, it will initially decrease speed, leading to the conclusion that certain options (C, D, E) cannot be correct. The conversation emphasizes the importance of understanding the distinction between speed and velocity in vector analysis. Ultimately, the challenge lies in finding the correct pair of vectors that meet the specified criteria.
kenji1992
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Vectors -- velocity is changing but speed is not...

Homework Statement


Which pair of vectors represent an object whose velocity is changing but whose speed is NOT changing?
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Homework Equations





The Attempt at a Solution



E? V is going left, indicating negative, while acceleration goes in the other direction.
 
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E? V is going left, indicating negative, while acceleration goes in the other direction.
But that acceleration is going to change the speed. It will, initially, decrease the speed. E is not correct.
 
#C, D, E can't be correct then by that logic... I hope I'm interpreting that correctly.
 
kenji1992 said:
#C, D, E can't be correct then by that logic... I hope I'm interpreting that correctly.
Right... and one more - which?
 

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