Science:Math Exam Resources/Courses/MATH102/December 2016/Question B 03 (b)
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Question B 03 (b) 

The velocity of a protein inside a cell starting at the top and falling under the force of gravity is given by the differential equation
where is the gravitational acceleration, is the acceleration due to drag and . (Note that this model ignores diffusion of the protein which makes it a really bad model but we’re exploring what gravity alone would do to a protein.) (b) For a cell in length from top to bottom, how long would it take (in seconds) for gravity alone to pull a protein across the cell if the protein moved at the whole time? 
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Hint 

Recall that . 
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Solution 

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Please rate my easiness! It's quick and helps everyone guide their studies. is the velocity of the protein traveling from the top to the bottom of the cell. The length is , and , so
