Geometrical Optics · Physics · WB JEE

The refractive indices of glass and quartz w.r.t. air are 3/2 and 12/5 respectively. The refractive index of quartz w.r.t. glass is

The radius of curvature of a concave mirror is 24 cm and the image is magnified by 1.5 times. The object distance is

A point source of light is kept at a depth of h in water of refractive index 4/3. The radius of the circle at the surface of water through which light emits is

A plano－convex lens fits exactly into a plano－concave lens．Their plane surfaces are parallel to each other．If lenses are made of different materials of refractive indices $\mu_1$ and $\mu_2$ and $R$ is the radius of curvature of the curved surface of the lenses，then the focal length of the combination is

A person has a minimum distance of distinct vision of 50 cm ．The power of lenses required to read a book at a distance of 25 cm is

Figure shows the graph of angle of deviation $\delta$ versus angle of incidence i for a light ray striking a prism. The prism angle is

Two convex lens $$(\mathrm{L}_1$$ and $$\mathrm{L}_2)$$ of equal focal length $$\mathrm{f}$$ are placed at a distance $$\frac{\mathrm{f}}{2}$$ apart. An object is placed at a distance $$4 \mathrm{f}$$ in the left of $$\mathrm{L_1}$$ as shown in figure. The final image is at

If $$\hat{n}_1, \hat{n}_2$$ and $$\hat{\mathrm{t}}$$ represent, unit vectors along the incident ray, reflected ray and normal to the surface respectively, then

When a convex lens is placed above an empty tank, the image of a mark at the bottom of the tank, which is 45 cm from the lens is formed 36 cm above the lens. When a liquid is poured in the tank to a depth of 40 cm, the distance of the image of the mark above the lens is 48 cm. The refractive index of the liquid is

Three identical convex lenses each of focal length $$\mathrm{f}$$ are placed in a straight line separated by a distance $$\mathrm{f}$$ from each other. An object is located at f/2 in front of the leftmost lens. Then,

The human eye has an approximate angular resolution of $$\theta$$ = 5.8 $$\times$$ 10^$$-$$4 rad and typical photo printer prints a minimum of 300 dpi (dots per inch, 1 inch = 2.54 cm). At what minimal distance d should a printed page be held so that one does not see the individual dots?

A ray of light travelling in air is incident on one face of a parallel glass slab of thickness $t$ and refractive index $\mu$ at an angle of incidence $i$ ．Total time spent by the ray inside the slab is

An electromagnetic wave，whose wave normal makes an angle of $45^{\circ}$ with the vertical，is travelling in air and strikes a horizontal liquid surface．While travelling through the liquid，it gets deviated by $15^{\circ}$ ．If the speed of electromagnetic wave in air is $3 \times 10^8 \mathrm{~m} / \mathrm{s}$ ，then the speed of electromagnetic wave in the liquid will be