Question

If eyepiece lens of a compound microscope is moved a little away from objective lens without changing positions of object and objective lens, then:
(A) image will not be formed
(B) final image will be real and erect with respect to the object
(C) Observer will see a sharp image
(D) final image will be diminished

Answer 1

Hint: A compound microscope contains 2 lenses. One of them is called the eyepiece and the other is called the objective lens. The light from the objective lens refracts the light rays onto the eye piece as an inverted image. This image is then magnified by the eye piece and the final image is formed behind the objective lens.

Complete step by step solution
In a compound microscope, there are 2 lenses. One of them is situated near the eye of the observer and is called the eye piece. The other is placed near the other end of the microscope near the object and is known as the objective lens. When the eyepiece of the lens is moved further away from the objective lens, the light ray might converge at a distance that is not within the focal length of the eye piece. If this happens the eye piece will form a virtual and inverted image. As the image gets inverted twice, the final result is an upright and real image.

Therefore, the correct answer is option B.

Note: Eyepiece and objective lens have different focal length or different apertures. Out of these 2, the focal length and aperture of the eyepiece is greater than that of the objective lens. This is done so that the eyepiece receives more light and the final image is bright enough.