Question about Average Velocities, vectors, kinematics

AI Thread Summary
The discussion revolves around a hill walker's average velocities while traveling west and then east. The walker initially covers 6.38 km at 2.81 m/s west, then turns around and walks east at 0.327 m/s. A calculation attempts to determine the distance walked east, but it lacks clarity due to missing units in the equations. A participant points out the importance of including units for accurate communication of the calculations. Clear representation of units is essential for understanding vector addition and kinematics in this context.
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1. In getting to his destination, a hill walker walks with an average velocity of 1.22 m/s due west. This is because he walks 6.38 km with an average velocity of 2.81 m/s due west, turns around 180 degrees and walks with an average velocity of 0.327 m/s due east. How far east did she walk (in km)



2. Vector addition/ subtraction



2.81 - 0.327 = 2.483
2.81 = 6,380
1 = 2270.46
2.483 = 5637.56


6380 - 5637.56 = 742.44

Can someone please confirm if this is right ?

 
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Welcome to PF.

It's unclear what you are trying to write, because you have left out units. Saying 2.81=6,380 is just plain false, it's like saying 1=2.

For example:
1 inch = 2.54 cm is a correct statement
1 = 2.54 is a false statement

If you were to include units in your equations, it might be clearer just what you're trying to say.
 

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