Mức quán tính của một vật quay quanh một trục không phụ thuộc vào

One answer could be erosion

The chemical reactions lab we did is typically called a "copper plating lab,  because the acid solution cleaned the pennies and made the copper look shinier;   the acid solution cleaned the paperclips and made them look like pennies;   &   the copper from the pennies was removed, and then added to the paperclips. 

Ray 2 should cross through the focal point on the right side of the lens