Resultant Displacement with direction problem

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The discussion revolves around calculating total running distance and resultant displacement after a 13-minute run involving two segments: running west at 4 m/s for 5 minutes and northeast at 2 m/s for 8 minutes. The total distance calculated is 2160 meters, but there is confusion regarding the resultant displacement. The user attempted to use trigonometry to find the vertical and horizontal components of the northeast segment but did not arrive at the correct answer. There is a suggestion that without showing the detailed calculations, it is difficult to identify the errors made. Accurate calculations and clear presentation of the work are essential for resolving the issue.
pennywise1234
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Homework Statement


You run towards the west with a velocity of 4 m/s for 5 minutes. You then continue running to the northeast (halfway between north and east) at 2 m/s for 8 minutes. (a) At the end of the 13 minute run , what was your total running distance? (b) At the end of the 13 minute run, what was your resultant displacement relative to your starting position?

Homework Equations


trig

The Attempt at a Solution


i got the total distance by converting minutes into seconds and multiply the number by each velocity i got 2160m for total running distance. i was unable to figure out the resultant i created the triangle with using 45 degrees as the angle (due to the north east reference), but i am not getting the answers similar to the answer keyi used the given numbers to find the vertical and horizontal components so i made my triangle with the 45 degree reference and 2m/s to find the horizontal and vertical components (i solved using trig) that did not due.i then tried using the numbers converted to seconds and that did not work either. So i used 960m/s to solve the triangle with the 45 degree reference . As that is the number you get when you multiple 2x60x8. I am also including the 4 or 1200(when multiplied) as an added horizontal component and did not get the right answer

where did i got wrong
 
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pennywise1234 said:
where did i got wrong
No way to tell if you do not post your working.
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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