MHTCET 20 Apr 2026 Shift 2 Paper

Concept:The resolving power of a compound microscope depends on the numerical aperture and the wavelength of light used.Explanation:The resolving power is given by the formula:$$RP = \frac{2n\sin\theta}{\lambda}$$Here, $n$ is the refractive index of the medium between the object and the objective lens.$\theta$ is the half-angle of the cone of light entering the objective lens.$\lambda$ is the wavelength of the light used.To improve the resolving power, we need to increase the value of $n\sin\theta$ or decrease the value of $\lambda$.Increasing the refractive index $n$ of the medium between the object and the objective lens increases the resolving power.This is the principle behind oil immersion objectives in high-resolution microscopy.Decreasing the diameter of the objective lens or increasing the wavelength would reduce the resolving power.Changing the focal length of the eyepiece does not directly improve the resolving power of the microscope.Answer:Option C: increase the refractive index of the medium between the object and objective lens.