Ray optics practice · Medium

The radius of curvature of each surface of a convex lens of refractive index 1.5 is $40 \mathrm{~cm}$. Calculate its power.

Near and far points of human eye are

Assertion: We cannot produce a real image by plane or convex mirrors under any circumstances.
Reason: The focal length of a convex mirror is always taken negative.

Given below are two statements:
Statement (I): When an object is placed at the centre of curvature of a concave lens, image is formed at the centre of curvature of the lens on the other side.
Statement (II): Concave lens always forms a virtual and erect image.
In the light of the above statements, choose the correct answer from the options given below:

The condition for an achromatic doublet, is (${f_1}\,\,{\text{and }}{f_2}$ are the focal lengths of individual lenses)

A beam of light converges towards a point $O, 10$ $\,{cm}$ behind a concave mirror of focal length 20 $\,{cm}$. Magnification produced by the mirror is

When light is passed through a prism, the colour which deviates least is -

A source of light lies on the angle bisector of two plane mirrors inclined at angle $\theta$. The values of $\theta$, so that the light reflected from one mirror does not reach the other mirror will be

An experiment is performed to find the refractive index of glass using a travelling microscope. In this experiment distances are measured by

Assertion: A double convex lens $(\mu=1.5)$ has focal length $10 \mathrm{~cm}$. When the lens is immersed in water $(\mu=4 / 3)$ its focal length becomes $40 \mathrm{~cm}$.
Reason: $\frac{1}{f}=\frac{\mu_1-\mu_m}{\mu_m}\left(\frac{1}{R_1}-\frac{1}{R_2}\right)$

The angular magnification of a simple microscope can be increased by increasing

An object is placed in front of a convex mirror of focal length $f$. Find the maximum and minimum distance of two object from the mirror such that the image is real and magnified.

Two plane mirrors are at right angles to each other. A man stands between them and combs his hair with his right hand. In how many of the images will he be seen using his right hand

A divergent lens will produce

A liquid wets a solid. The meniscus of the liquid in a long vertical capillary tube of that solid is

A thin sheet of glass $(\mu=1.5)$ of thickness 6 microns introduced in the path of one of interfering beams in a double slit experiment shifts the central fringe to a position previously occupied by fifth dark fringe. Then the wavelength of light used is:

Which of the following quantity remains unchanged after refraction?

The focal lengths of the objective and eyelenses of a microscope are $\mathrm{1}\mathrm{.6 }\,\mathrm{cm}$ and $\mathrm{2}\mathrm{.5 }\,\mathrm{cm}$ respectively. The distance between the two lenses is $\mathrm{21}\mathrm{.7 }\,\mathrm{cm}$. If the final image is formed at infinity, the distance between the object and the objective lens is

The refractive indices of water and glass with respect to air are $4 / 3$ and $5 / 3$, respectively. The refractive index of glass with respect to water will be

Sam is standing in front of a reflecting surface and he observes that his image formed by the surface is virtual, erect and magnified. The reflecting surface is a;

If the angle of minimum deviation is ${60^0}$ for an equilateral prism, then the refractive index of the material of the prism is

Transmission of light to large distances through optical fibres is based on

A convex lens made of material of
refractive index 1.5 and having a focal length of
10 cm is immersed in a liquid of refractive index
3.0. The lens will behave as

When sunlight is scattered by atmospheric atoms and molecules, the amount of scattering of light of wavelength $\mathrm{440}\,\,\mathrm{nm}$ is $A$. The amount of scattering for the light of wavelength $\mathrm{660}\,\,\mathrm{nm}$ is approximately

With a concave mirror, an object is placed at a distance ${x_1}$ from the principal focus, on the principal axis. The image is formed at a distance ${x_2}$ from the principal focus. The focal length of the mirror is

By taking large aperture objective in telescope
helps in

Focal length of a convex lens will be maximum for

The field of view is maximum for

An object is moving with speed $v_0$ towards a spherical mirror with radius of curvature $R$, along the central axis of mirror. The speed of the image with respect to the mirror is ( $U$ is the distance of the object form mirror at any given time $t$ )

Two transparent slabs having equal thickness but different refractive indices $\mu_1$ and $\mu_2$ are pasted side by side to form a composite slab. This slab is placed just after the double slit in a Young's experiment so that the light from one slit goes through one material and the light from the other slit goes through the other material. What should be the minimum thickness of the slab so that there is a minimum at the point $P_0$ which is equidistant from the slits?