How to find the missing displacement (vectors)?

AI Thread Summary
To find the missing displacement vector for the hikers' third day, start by drawing a vector diagram to visualize their movements. The total displacement after three days is 30 km north, which is the resultant vector. The first day's hike was 20 km east, and the second day involved a hike of 30 km at 53 degrees north of west. By analyzing the north-south and east-west components separately, you can sum the displacements in each direction to solve for the third day's displacement. Providing more detailed calculations will facilitate better assistance in solving the problem.
marbille9
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Homework Statement



After three days of hiking, a group of hikers are 30km N from their starting position. On the first day, they hiked 20km E. On the second day, they hiked 30km 53 degrees N of W, calculate their displacement on the third day.

Homework Equations



I haven't a single clue

The Attempt at a Solution

 
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Hi marbille9, welcome to PF.

Start by drawing the vector diagram out...The final displacement is the vectorial sum of their displacements on each day.
 
30km N is the resultant vector. But I don't kow how to find the displacement on the third day.
 
marbille9 said:
30km N is the resultant vector. But I don't kow how to find the displacement on the third day.

Well, the displacements in the north-south direction don't effect the displacements in east-west direction. Sum the individual displacements in each direction (i.e NS, and WE) and equate the NS to 30, and the WE sum to 0...


PS : You need to show some more work, so that you can be helped better :wink:
 
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