Solve Kinematics Problem: Initial Velocity of Jogger

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Homework Help Overview

The problem involves a jogger who accelerates to a velocity of +2.3 m/s over a period of 6.5 seconds and then travels a distance of 11 meters before stopping. The main question is to determine the initial velocity of the jogger. There is some confusion regarding the final velocity and the interpretation of the distance traveled.

Discussion Character

  • Exploratory, Problem interpretation, Assumption checking

Approaches and Questions Raised

  • Participants discuss the interpretation of the problem, particularly the final velocity and the meaning of the 11 meters traveled. There are attempts to clarify the wording and intent of the problem statement. Some suggest starting from rest to analyze the jogger's motion.

Discussion Status

The discussion is ongoing, with participants seeking clarification on the problem's wording and the expected answer. Some guidance has been offered regarding the kinematic equations that may be relevant, but there is no consensus on the interpretation of the jogger's motion or the final velocity.

Contextual Notes

Participants note that the problem may be poorly worded, leading to confusion about the jogger's acceleration and stopping conditions. There is also mention of the absence of provided answers, which may impact the interpretation of the problem.

Ksenia
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Okay so I have tried for hours to figure this out and can't. Please show me how to get the answers; what do I already have, what do I need, and what kinematics formula(s) do I use? Thanky ou so much!
Problem:
A jogger accelerates constantly to a velocity of +2.3m/s in 6.5s. After jogging 11m, the jogger stops. What was the initial velocity of the jogger?
I can use any rearrangement of the 5 kinematics formulas (each one only has 4 variables) to solve this question.
I do not understand if the final velocity is 0m/s or 2.3m/s. And does the 11m come after he accelerates or is the 11m the total distance that was traveled?
 
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Ksenia said:
I do not understand if the final velocity is 0m/s or 2.3m/s. And does the 11m come after he accelerates or is the 11m the total distance that was traveled?

I can't interpret the problem either. Did you quote it exactly?
 
Ksenia said:
A jogger accelerates constantly to a velocity of +2.3m/s in 6.5s. After jogging 11m, the jogger stops. What was the initial velocity of the jogger?
Hi Ksenia. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

We could recast this data into a legitimate kinematics question. But I would like to see the original wording just the same.

Do you know what answer they are looking for?
 
Last edited by a moderator:
Stephen Tashi said:
I can't interpret the problem either. Did you quote it exactly?
Yes I worded it just like it was in the problem. And no there are no answers as this came from my correspondence module
:(
 
NascentOxygen said:
Hi Ksenia. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

We could recast this data into a legitimate kinematics question. But I would like to see the original wording just the same.

Do you know what answer they are looking for?
No, the answer isn't given and the wording is exactly as in my booklet.
 
Last edited by a moderator:
Why not, as a start, work out how far the jogger would travel if they started from rest and accelerated as described.
 
Ksenia said:
Yes I worded it just like it was in the problem. And no there are no answers as this came from my correspondence module
:(

My guess is that "After jogging 11m, the jogger stops" is a badly written sentence that should have been worded to convey the idea that during the time the jogger is accelerating he travels 11 meters. So he "stops accelerating" not "stops moving".

If you following the template for homework, you will state the 5 kinematic equations. My guess is that your are expected to work with v = v_0 + (a)(t) and d = d0 + v_0 t + (1/2)(a)(t^2) where we take d_0 = 0 as the distance where the jogger began accelerating.
 

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