Help with magnetic induction and finding induced current

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The discussion focuses on a practice test problem involving a loop of wire moving into a magnetic field, with participants trying to determine the direction of induced current at specific points. The Right Hand Rule and Lenz's Law are referenced as key concepts for solving the problem. There is confusion regarding the behavior of magnetic flux at point D, particularly whether it is increasing or decreasing as the loop enters the magnetic field. Participants clarify that while the magnetic field may be constant, the area of the loop interacting with the field changes, affecting the magnetic flux. The conversation emphasizes understanding the relationship between magnetic flux, area, and the direction of induced current.
mick5000x
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Homework Statement


I have attached a picture that details the problem. This is my practice test and I have no clue what I am doing wrong. Essentially a loop of wire is moving in constant velocity into a magnetic field. The magnetic field lines are pointing into the page. The problem is asking which at which points is the loop's induced current flowing clockwise and counterclockwise. I do not need the answer for 14 and 15.
qAKMRWX.jpg

Homework Equations


Lenz Law
Right Hand Rule

The Attempt at a Solution


I attempted to use right hand rule, where my thumb points in the direction of the current. I figured out that if you point your thumb in the counterclockwise direction current of B, it will give you an upward magnetic field inside the loop, which is exactly what I wanted. However, I cannot figure out why D is moving in the clockwise position because if I try the right hand rule, it will point inside the loop, the same direction as the magnetic field.
 

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Welcome to PF!

Is the magnetic flux through the loop increasing or decreasing at D?
 
Thanks for the welcome! Isn't the magnetic field constant throughout, meaning the magnetic flux is constant? Or does magnetic flux decreases along the X axis even though magnetic field is constant?
 
How would you determine the magnetic flux through the loop at the instant when the loop is at D?
 
From what I understand, magnetic flux is equal to B * A, where B is the magnetic field that is perpendicular to the surface, and A is the surface area. Does this mean the change in magnetic flux between the two halves of D causes magnetic flux to decrease?
 
When using Φ = BA at point D, the area A is the area inside the loop where B is nonzero. The region where B = 0 inside the loop does not contribute to the magnetic flux through the loop.
 
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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