JEE Main 2024 (Online) 4th April Morning Shift | Geometrical Optics Question 9 | Physics

In an experiment to measure focal length ($$f$$) of convex lens, the least counts of the measuring scales for the position of object (u) and for the position of image (v) are $$\Delta u$$ and $$\Delta v$$, respectively. The error in the measurement of the focal length of the convex lens will be:

$$2 f\left[\frac{\Delta \mathrm{u}}{\mathrm{u}}+\frac{\Delta \mathrm{v}}{\mathrm{v}}\right]$$

$$f\left[\frac{\Delta \mathrm{u}}{\mathrm{u}}+\frac{\Delta \mathrm{v}}{\mathrm{v}}\right]$$

$$f^2\left[\frac{\Delta \mathrm{u}}{\mathrm{u}^2}+\frac{\Delta \mathrm{v}}{\mathrm{v}^2}\right]$$

$$\frac{\Delta \mathrm{u}}{\mathrm{u}}+\frac{\Delta \mathrm{v}}{\mathrm{v}}$$

JEE Main 2024 (Online) 31st January Morning Shift

MCQ (Single Correct Answer)

-1

The refractive index of a prism with apex angle $$A$$ is $$\cot A / 2$$. The angle of minimum deviation is :

$$\delta_m=180^{\circ}-3 \mathrm{~A}$$

$$\delta_m=180^{\circ}-4 A$$

$$\delta_m=180^{\circ}-2 A$$

$$\delta_m=180^{\circ}-A$$

JEE Main 2024 (Online) 29th January Evening Shift

MCQ (Single Correct Answer)

-1

If the distance between object and its two times magnified virtual image produced by a curved mirror is $$15 \mathrm{~cm}$$, the focal length of the mirror must be:

$$-10$$ cm

$$-12$$ cm

15 cm

10/3 cm

JEE Main 2024 (Online) 29th January Morning Shift

MCQ (Single Correct Answer)

-1

A convex mirror of radius of curvature $$30 \mathrm{~cm}$$ forms an image that is half the size of the object. The object distance is :

$$-$$45 cm

$$-$$15 cm

45 cm

15 cm