Size and direction of the change in velocity

AI Thread Summary
The discussion focuses on calculating the change in velocity for three scenarios. For the first case, the change from 5 m/s west to 10 m/s west results in a 5 m/s increase west. In the second case, the change from 10 m/s west to 5 m/s west shows a decrease of 5 m/s, which is interpreted as a change to the opposite direction, east. The third scenario, changing from 5 m/s west to 10 m/s east, leads to confusion; the book states the change is 15 m/s east, which is explained by treating west as negative and east as positive, resulting in a total change of 15 m/s. This highlights the importance of understanding directional velocity changes in physics.
coconut88
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Homework Statement


Find Size and direction of the change in velocity:

a)5m/s west to 10 m/s west

b)10m/s west to 5m/s west

c)5m/s west to 10m/s east

Homework Equations





The Attempt at a Solution



a)10-5= 5 west

b)5-10=-5 because there isn't size wihe negitve the answer will be 5 to oppicite direction (east)

C) My problem here the book says the answer will be 15 m/s east but I don't how it come up with it ?

can you explain it for me ?
 
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coconut88 said:

Homework Statement


Find Size and direction of the change in velocity:

a)5m/s west to 10 m/s west

b)10m/s west to 5m/s west

c)5m/s west to 10m/s east

Homework Equations





The Attempt at a Solution



a)10-5= 5 west

b)5-10=-5 because there isn't size wihe negitve the answer will be 5 to oppicite direction (east)

C) My problem here the book says the answer will be 15 m/s east but I don't how it come up with it ?

can you explain it for me ?

5m/s west is equal to -5m/s east.
 
Think you FedEx
5m/s west to 10m/s east = 15 m/s east here my problem
From where I can get 15? why does the book add them?even I know that if I want to know finall velocity v2-v1 but here v2+v1 why ?
 
coconut88 said:
Think you FedEx
5m/s west to 10m/s east = 15 m/s east here my problem
From where I can get 15? why does the book add them?even I know that if I want to know finall velocity v2-v1 but here v2+v1 why ?

(10m/s east) - (5 m/s west) = (10 m/s east) - (- 5m/s east) = 15 m/s east
 

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