Final answer:
The magnification in a microscope is not directly influenced by the physical length of the objective lens but instead depends on the focal lengths of the objective and eyepiece lenses, and changes in the lens-to-object distance.
Step-by-step explanation:
The statement that the longer the objective of the microscope, the greater the magnification of the lens is false. In a compound microscope, the total magnification is the product of the magnification of the objective lens and the angular magnification provided by the eyepiece. As per your question, the microscope's objective lens magnification can be affected by changing the distance between the object and the objective lens. However, the length of the objective lens itself typically refers to its physical size rather than its focal length, which is the main factor affecting magnification along with the eyepiece's focal length.
Magnification in microscopes is more complexly related to the focal lengths of the two lenses used - the objective and the ocular (eyepiece) lens. The magnification of the objective lens (mobj) is obtained from the thin-lens equation and the total magnification is then calculated by multiplying mobj with the angular magnification (Meye) of the eyepiece. Therefore, the changes in lens-to-object distances, as described in your scenario, will change the magnification, but it does not directly pertain to the physical length of the objective lens.