Ray Optics and Optical Instruments

When light travels from water ($n=1.33$) to glass ($n=1.5$), it bends:

Snell's law is mathematically expressed as:

If the refractive index of a medium is $\sqrt{2}$, what is its critical angle with respect to air?

The apparent shift of an object viewed through a glass slab depends on:

When a light ray enters from air to a medium of refractive index $n$ at an angle of incidence $i$, the maximum possible angle of refraction is:

If the wavelength of light changes from $7000$ Å to $3500$ Å as it moves from medium 1 to medium 2, the refractive index of medium 2 with respect to medium 1 is:

The refractive index of water is $1.33$ and for glass it is $1.5$. Light travels from glass to water. The critical angle is:

A ray of light is incident on a medium of $n = \sqrt{2}$ from air. If the angle of incidence is $45^\circ$, what is the deviation of the ray?

A container is filled with a liquid of refractive index $n$ to a height $H$. A point source is placed at the bottom. What is the area of the surface of the liquid through which light from the source can emerge?

A ray of light is incident normally on the face $AB$ of a $30-60-90$ prism $ABC$ (angle $A=90, B=60, C=30$). If the material of the prism has $n = 1.5$, which face does the ray exit from?

If the focal length of a lens in air is $f_{air}$ and its refractive index is $1.5$, what happens to $f$ if it is placed in a medium with $\mu = 1.5$?

For a biconvex lens, the second surface ($R_2$) has its center of curvature on the:

A lens has a focal length of $50$ cm. What is its power?

If a lens is placed in a medium with a refractive index $\mu_m$ and the lens material index is $\mu_l$, the term $(\mu - 1)$ becomes:

If the power of an equiconvex lens is $+2\text{ D}$ and the refractive index of the glass is $1.5$, what is the radius of curvature $R$ of each surface?

A biconvex lens with $R_1 = 10\text{ cm}$ and $R_2 = -10\text{ cm}$ and $n = 1.5$ is immersed in a liquid with $n = 1.5$. The focal length is:

A biconvex lens with $n = 1.5$ is in air. If it is moved to a medium with $n = 1.2$, the focal length increases by a factor of:

What is the focal length of a biconvex lens ($n=1.5$) if the radius of curvature of each surface is equal to its focal length?

A lens has a power $P$ in air. If it is immersed in a liquid whose refractive index is $n_l$, and the lens material has index $n_g$, the new power $P'$ is zero when:

A biconvex lens of focal length $20\text{ cm}$ has radii of curvature $R$ and $2R$. If $n=1.5$, find the value of $R$.

Which of the following is used to measure the refractive index of a liquid using a hollow prism?

The deviation produced by a prism is zero if:

When light enters a prism, the emergent ray is:

The shape of the graph plotted between the angle of incidence ($i$) and the angle of deviation ($\delta$) is:

Which of the following graphs correctly represents the variation of the angle of deviation ($\delta$) with the angle of incidence ($i$) for a prism?

If a prism has a refracting angle of $60^{\circ}$ and refractive index $\mu = 2$, the angle of minimum deviation is:

A ray of light is incident at an angle $i$ on a prism of angle $A$. If the refracted ray inside the prism is perpendicular to the bisector of the angle of prism, then:

A prism of angle $A$ is made of a material whose refractive index $n$ varies with wavelength $\lambda$. For which wavelength will the deviation be minimum?

If a ray is incident normally on one face of an equilateral prism of refractive index $1.5$, the deviation produced is:

A thin prism $P_1$ with angle $4^\circ$ and $n=1.54$ is combined with another thin prism $P_2$ with $n=1.72$ to produce dispersion without deviation. The angle of prism $P_2$ is:

In a simple microscope, if the focal length is decreased, the magnifying power:

Which of the following is correct for a telescope in normal adjustment?

The final image formed by an astronomical telescope for a normal eye (infinity) is:

A telescope has an objective of aperture $10\text{ cm}$. If the aperture is increased to $20\text{ cm}$, the light gathering power becomes:

For a telescope in normal adjustment, if the focal length of the objective is $f_o = 1.2\text{ m}$ and the focal length of the eyepiece is $f_e = 3\text{ cm}$, the tube length is:

A simple microscope consists of a single convex lens. If the object is placed at the focal point of the lens, the final image is formed at:

Which of the following colors of light would provide the highest resolving power for a microscope, assuming all other factors are constant?

The magnifying power of an astronomical telescope in normal adjustment is $100$ and the distance between objective and eyepiece is $101\text{ cm}$. The focal lengths of objective and eyepiece are:

What is the magnifying power of a compound microscope with $f_o = 1\text{ cm}$, $f_e = 5\text{ cm}$ and an object placed at $1.1\text{ cm}$ from the objective? The image is formed at the near point ($25\text{ cm}$).

In an astronomical telescope, the aperture of the objective is made large to:

The relation $R = 2f$ is valid for:

The image of a distant tree in a small convex mirror is:

If the object is at $2F$ (or C) of a concave mirror, the image is:

Searchlights use which type of mirror?

A small needle of length $2 \text{ mm}$ is placed along the principal axis of a concave mirror of focal length $10 \text{ cm}$ such that its center is at a distance of $15 \text{ cm}$ from the pole. Using the method for longitudinal magnification shown in the flowchart, what is the length of the image of the needle?

A spherical mirror is cut from a glass sphere of radius $40$ cm. What is the focal length of this mirror?

If the focal length of a concave mirror is $20$ cm, the radius of curvature is:

A light ray parallel to the principal axis is incident on a concave mirror of radius $R$. After reflection, it intersects the axis at a point $F$. As the distance of the incident ray from the axis increases, the distance $PF$:

A real object is placed at a distance $u$ from a mirror. The focal length is $f$. The magnification is $m$. The relationship between $u, f,$ and $m$ is:

A concave mirror has a radius of curvature $R$. For a point object on the axis at distance $u$, the image distance is $v$. If $u$ is increased by a small amount $\Delta u$, then $v$ decreases by $\Delta v$. The ratio $\Delta v / \Delta u$ is:

A point object is placed on the principal axis of a convex lens. The number of images formed is:

For a convex lens, when the object is moved from $2F$ towards $F$, the size of the real image:

The formula $m = v/u$ for a lens indicates that if $m$ is positive, the image is:

A magnifying glass is usually a:

A point object is placed in air ($n_1 = 1$) at a distance of $2R$ from the vertex of a convex spherical refracting surface of radius of curvature $R$. If the refractive index of the material of the surface is $n_2 = 1.5$, at what distance from the vertex will the image be formed?

For a convex lens, which of the following object positions produces a virtual image?

A glass sphere of radius $R$ has a small bubble at its center. The apparent position of the bubble when seen from outside is:

In the displacement method, the magnification in the two positions are $m_1$ and $m_2$. The focal length $f$ of the lens is given by:

A lens of refractive index $n$ is immersed in a liquid of refractive index $n$. Its focal length will be:

A glass sphere of radius $R$ and refractive index $1.5$ has an object at a distance $2R$ from its surface. The final image is formed at a distance $v$ from the second surface. What is $v$?