(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The bacterium Escherichia coli (or E. coli) is a single-celled organism that lives in the gut of healthy humans and animals. When grown in a uniform medium rich in salts and amino acids, these bacteria swim along zig-zag paths at a constant speed of 20 um/s. The figure shows the trajectory of an E. coli as it moves from point A to point E. Each segment of the motion can be identified by two letters, such as segment BC.

2. Relevant equations

Displacement of segment=√(segment_{x}^{2}+segement_{y}^{2})

θ=tan^{-1}(segment_{y}/segment_{x})

v=displacement/Δt

3. The attempt at a solution

Because I think my confusion can be cleared with just on portion of this problem, let's use vector AB. Here is the question I am trying to answer: Calculate the x- and y- components of its displacement and of its velocity.

I have AB_{x}=50μm, and AB_{y}=10μm

The displacement is 50.99μm, 11° NE

The problem is finding the velocity, I don't know how to do it in this instance? It doesn't give a time really, just the constant speed of 20μm/s. I can't help but to think that I'm missing something completely obvious, but I just can't figure out what to do?

Thank you for any help!

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# Finding the velocities of these segments?

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