Concave Mirror and objects distance

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A concave mirror with a focal length of 44 cm produces an image at a distance that is one-fourth of the object distance. To solve for the object distance (do) and image distance (di), the equation 1/do + 1/di = 1/f is used. The confusion arises regarding the relationship between di and do, specifically whether di should be expressed as 1/4do or 4do. Clarification is needed on the correct interpretation of the image distance in relation to the object distance. Understanding these relationships is crucial for accurately determining both distances.
sheri1987
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Homework Statement


A concave mirror (f = 44 cm) produces an image whose distance from the mirror is one-fourth the object distance.

(a) Determine the object distance.
cm

(b) Determine the (positive) image distance.
cm



Homework Equations



1/do +1/di =1/f do=object distance and di=image distance


The Attempt at a Solution



Since there are two unknowns I thought I could change the equation to 1/do + 1/4do = 1/f...and solve but this wasn't turning out right? am I going about this the wrong way?
 
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Is 1/4do equal to (1/4)do or 1/(4do)? In any case, if the image distance is one-fourth the object distance, does that mean that di = 4do?
 
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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