Relative Velocity in River Navigation: Solving for Current and Boat Speed

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The discussion focuses on solving a physics problem involving relative velocity in river navigation. A boat is moving at 6.0 m/s due north at an angle of 53 degrees west of north, while the river flows east. Participants suggest drawing a diagram to visualize the vectors and break them into x and y components. The calculations yield a current velocity of 8 m/s and a boat speed relative to the water of 10 m/s, which are confirmed as correct. The problem exemplifies the application of trigonometry in analyzing vector relationships in navigation scenarios.
Jacobpm64
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I'm not sure how to do this problem.. please help..

A river flows toward the east. Because of your knowledge of physics, you head your boat 53 degrees west of north and have a velocity of 6.0 m/s due north relative to the shore.
a. What is the velocity of the current.
b. What is your speed relative to the water?
 
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Velocities are vectors.
Draw a diagram and divide the velocities into x and y components.
 
Almost the same answer: draw a picture showing the vectors: the boat's velocity relative to the shore, the river current's velocity, and the boat's velocity relative to the current. Look at the right triangle you have just drawn and use trigonometry.
 
I ended up getting
a. 8m/s
b. 10m/s

Is this correct? it looks like a 6,8,10 triangle to me.
 
Yes, they are correct.
 
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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