What is the cyclist's end position? I know his displacement.

AI Thread Summary
The cyclist maintains a constant velocity of 5.3 m/s and starts 259 m from point A. After 83 seconds, the displacement from his starting position is calculated to be 439.9 m. To find his position from point A, the cyclist's initial distance (259 m) must be added to the displacement (439.9 m), resulting in a total position of 698.9 m from point A. The discussion emphasizes the importance of correctly interpreting displacement versus position. Ultimately, the cyclist's final position from point A is confirmed to be 698.9 m.
AVReidy
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Homework Statement



I can't figure out part two to a problem. The first part asked us to find the displacement, but I'll let you read for yourselves:

Part 1: A cyclist maintains a constant velocity of
5.3 m/s headed away from point A. At some
initial time, the cyclist is 259 m from point A.
What will be his displacement from his
starting position after 83 s?
Answer in units of m

Part 2: What will be his position from point A after
that time?
Answer in units of m

I solved part 1 and my answer was (from point A)\Deltax = 439.9m which I know is correct.

Homework Equations



I didn't use an equation, I just did it in steps that I made up. Maybe xf = vt + xi would work?

The Attempt at a Solution



I solved part 1 by dividing the cyclist's distance from point A (259m) by his velocity (5.3m/s) to get the seconds it took (48.8679) to travel 259m. I then set up a proportion with these values to solve for the displacement that the question was asking for, which was 439.9m.

I'm not sure how to find out what his position will be at 83s. I thought it might have been identical to the displacement, but there is really no given starting point value... It wouldn't be 439.9 + 259, would it? I feel like they left out the starting position value. Maybe A + 439.9?

Any help would be greatly appreciated!
 
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AVReidy said:

Homework Statement



I can't figure out part two to a problem. The first part asked us to find the displacement, but I'll let you read for yourselves:

Part 1: A cyclist maintains a constant velocity of
5.3 m/s headed away from point A. At some
initial time, the cyclist is 259 m from point A.
What will be his displacement from his
starting position after 83 s?
Answer in units of m

Part 2: What will be his position from point A after
that time?
Answer in units of m

I solved part 1 and my answer was (from point A)\Deltax = 439.9m which I know is correct.

Homework Equations



I didn't use an equation, I just did it in steps that I made up. Maybe xf = vt + xi would work?

The Attempt at a Solution



I solved part 1 by dividing the cyclist's distance from point A (259m) by his velocity (5.3m/s) to get the seconds it took (48.8679) to travel 259m. I then set up a proportion with these values to solve for the displacement that the question was asking for, which was 439.9m.

I'm not sure how to find out what his position will be at 83s. I thought it might have been identical to the displacement, but there is really no given starting point value... It wouldn't be 439.9 + 259, would it? I feel like they left out the starting position value. Maybe A + 439.9?

Any help would be greatly appreciated!

It would be that yes.
 
Thanks! I always end up figuring it out (sometimes without realizing it) when I write out my thoughts here. Thanks!
 
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