Simple,quick relative velocity question?

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The boat is traveling at 10 m/s relative to the ground, while the sea is moving at 5 m/s in the same direction. To find the speed of the boat relative to the sea, the equation used is v_B/S = v_B - v_S, resulting in a relative speed of 5 m/s. This means a person in the sea would perceive the boat moving at 5 m/s. The confusion arises from distinguishing between the boat's speed relative to the ground and its speed relative to the water.
sameeralord
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Hello I'll make it quick

Boat is traveling at 10m/s the sea is traveling at 5m/s. What is the speed of the boat relative to the sea and why?

Through vectors I worked it out to be 10m/s(not sure) but shouldn't it be five because if a person is standing in the sea and sees the boat it would be traveling at 5m/s.

The ship relative to the ground is 15m/s right.

Thank you!
 
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B=boat
S=Sea
G=ground.

B/S= Boat relative to Sea


I assume if there is a diagram it looks like this


--------> boat
----> sea

\vec{v}_{B/S}=\vec{v}_B-\vec{v}_S = 10-5=5 m/s


So the boat 'feels' as if it is traveling at 5m/s instead of 10m/s
 
rock.freak667 said:
B=boat
S=Sea
G=ground.

B/S= Boat relative to Sea


I assume if there is a diagram it looks like this


--------> boat
----> sea

\vec{v}_{B/S}=\vec{v}_B-\vec{v}_S = 10-5=5 m/s


So the boat 'feels' as if it is traveling at 5m/s instead of 10m/s

Thank you for your help. Isn't it 15m/s-10m/s. That is where my confusion lies. Isn't the boat relative to the ground 15m/s(someone in the shore would feel the boat traveling at 15m/s). When you are in the boat do you feel the resultant velocity or the actual velocity.
 
sameeralord said:
Boat is traveling at 10m/s
With respect to what? The water or the ground? And in what direction?
the sea is traveling at 5m/s.
Presumably with respect to the ground.
 
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