WBJEE PYQs for Ray optics and optical instruments with Solutions: Practice WBJEE Previous Year Questions

Updated 3+ months ago

Ray optics and optical instruments is an important topic in the Physics section in WBJEE exam. Practising this topic will increase your score overall and make your conceptual grip on WBJEE exam stronger.

This article gives you a full set of WBJEE PYQs for Ray optics and optical instruments with explanations for effective preparation. Practice of WBJEE Physics PYQs including Ray optics and optical instruments questions regularly will improve accuracy, speed, and confidence in the WBJEE 2026 exam.

WBJEE PYQs for Ray optics and optical instruments with Solutions

1.
A parallel beam of light is incident on a glass prism in the shape of a quarter cylinder of radius $R \,= \,0.05\, m$ and refractive index n = $1.5$ placed on a horizontal table as shown in the figure. Beyond the cylinder, a patch of light is found whose nearest distance $x$ from the cylinder is
- $\left(3\sqrt{3}-4\right)\times10^{-2}m$
- $\left(2\sqrt{3}-2\right)\times10^{-2}m$
- $\left(3\sqrt{5}-5\right)\times10^{-2}m$
- $\left(3\sqrt{2}-3\right)\times10^{-2}m$
View Solution
2.
There is a small air bubble at the center of a solid glass sphere of radius $r$ and refractive index $\mu$. What will be the apparent distance of the bubble from the centre of the sphere, when viewed from outside?
- $r$
- $\frac{r}{\mu}$
- $r(r - \frac{1}{\mu})$
- 0
View Solution
3.
A biconvex lens of focal length $f$ and radii of curvature of both the surfaces $R$ is made of a material of refractive index $n_1$. This lens is placed in a liquid of refractive index $n_2$. Now this lens will behave like
- either as a convex or as a concave len depending solely on R
- a convex lens depending on $n_1$ and $n_2$
- a concave lens depending on $n_1$ and $n_2$
- a convex lens of same focal length irrespective of R, $n_1$ and $n_2$
View Solution
4.
A diver at a depth of $12\, m$ in water $\bigg(\mu = \frac{4}{3}\bigg)$ sees the sky in a cone of semi vertical angle
- $\sin^{-1} \bigg(\frac{4}{3}\bigg)$
- $\tan^{-1} \bigg(\frac{4}{3}\bigg)$
- $\sin^{-1} \bigg(\frac{3}{4}\bigg)$
- $ 90^\circ $
View Solution
5.
Three identical convex lenses each of focal length f are placed in a straight line separated by a distance f from each other. An object is located in $\frac{f}{2}$ in front of the leftmost lens. Then,
- The final image will be at f/2 behind the rightmost lens and it's magnification will be -1
- The final image will be at f/2 behind the rightmost lens and it's magnification will be -1
- The final image will be at f behind the rightmost lens and it's magnification will be -1
- The final image will be at f behind the rightmost lens and it's magnification will be +1
View Solution
6.
A ray of monochromatic light is incident on the plane surface of separation between two media X and Y with the angle of incidence 'i' in medium X and angle of refraction 'r' in medium Y. The given graph shows the relation between sin i and sin r. If V_x and V_y are the velocities of the ray in media X and Y respectively, Then which of the following is true?
- V_x=$\frac{1}{\sqrt3}$V_y
- V_x=$\sqrt3$V_y
- Total internal reflection can happen when the light is incident in medium X.
- V_x=$\sqrt3$V_y, where V_x and V_y are frequencies of the light and medium X and Y respectively.
View Solution
7.
If the velocity of light in vacuum is $3\times10^{8}\, ms^{-1},$ the time taken (in nanosecond) to travel through a glass plate of thickness $10 \,cm$ and refractive index $1.5$ is
- 0.5
- 1
- 2
- 3
View Solution
8.
A glass slab consists of thin uniform layers of progressively decreasing refractive indices $RI$ (see figure) such that the $RI$ of any layer is $\mu-m\Delta \mu$. Here $\mu$ and $\Delta \mu$ denote the $RI$ of $0^{th}$ layer and the difference in $RI$ between any two consecutive layers, respectively. The integer $m = 0, 1, 2, 3.....$ denotes the numbers of the successive layers. A ray of light from the 0th layer enters the $1^{st}$ layer at an angle of incidence of $30^\circ$. After undergoing the $m^{th}$ refraction, the ray emerges parallel to the interface. If $\mu = 1.5$ and $\Delta \mu = 0.015$, the value of $m$ is
- 20
- 30
- 40
- 50
View Solution
9.
A ray of light is incident at an angle $i$ on a glass slab of refractive index $\mu$. The angle between reflected and refracted light is $90^{\circ}$. Then, the relationship between $i$ and $\mu$ is
- $i=\tan ^{-1}\left(\frac{1}{-\mu}\right)$
- $\tan \, i = \mu$
- $\sin \, i = \mu$
- $\cos \, i = \mu$
View Solution
10.
If $\vec{n}_1$, $\vec{n}_2$, and $\vec{i}$ represent unit vectors along the incident ray, reflected ray, and normal to the surface, respectively, then:
- $\vec{n}_2 = \vec{n}_1 - 2(\vec{n}_1 \cdot \hat{t})\hat{t}$
- $\vec{n}_2 = \vec{n}_1 + 2(\vec{n}_1 \cdot \hat{t})\hat{t}$
- $\vec{n}_2 = -\vec{n}_1$
- $\vec{n}_2 = 2\vec{n}_1 - (\vec{n}_1 \times \hat{t})$
View Solution
11.
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:
- 1.353
- 1.544
- 1.472
- 1.366
View Solution
12.
An object placed in front of a concave mirror at a distance of $x \,cm$ from the pole gives a $3$ times magnified real image. If it is moved to a distance of $(x+5)\, cm$, the magnification of the image becomes $2$. The focal length of the mirror is
- 15 cm
- 20 cm
- 25 cm
- 30 cm
View Solution
13.
The intermediate image formed by the objective of a compound microscope is
- real, inverted and magnified
- real, erect and magnified
- virtual, erect and magnified
- virtual, inverted and magnified
View Solution
14.
If the focal length of the eye-piece of a telescope is doubled, its magnifying power $(m)$ will be
- $2m$
- $3m$
- $\frac{m}{2}$
- $4m$
View Solution
15.
Two convex lenses ($L_1$ and $L_2$) of equal focal length $f$ are placed at a distance $\frac{f}{2}$ apart. An object is placed at a distance $4f$ to the left of $L_1$ as shown in the figure. The final image is at:
- $\frac{5f}{11}$ right of $L_2$
- $\frac{5f}{11}$ left of $L_2$
- $5f$ right of $L_2$
- $5f$ left of $L_2$
View Solution

View more WBJEE Questions

SHARE ON FACEBOOK SHARE ON TWITTER

WBJEE PYQs for Ray optics and optical instruments with Solutions: Practice WBJEE Previous Year Questions

WBJEE PYQs for Ray optics and optical instruments with Solutions

1.
A parallel beam of light is incident on a glass prism in the shape of a quarter cylinder of radius $R \,= \,0.05\, m$ and refractive index n = $1.5$ placed on a horizontal table as shown in the figure. Beyond the cylinder, a patch of light is found whose nearest distance $x$ from the cylinder is

2.
There is a small air bubble at the center of a solid glass sphere of radius \(r\) and refractive index \(\mu\). What will be the apparent distance of the bubble from the centre of the sphere, when viewed from outside?

3.
A biconvex lens of focal length $f$ and radii of curvature of both the surfaces $R$ is made of a material of refractive index $n_1$. This lens is placed in a liquid of refractive index $n_2$. Now this lens will behave like

4.
A diver at a depth of $12\, m$ in water $\bigg(\mu = \frac{4}{3}\bigg)$ sees the sky in a cone of semi vertical angle

5.
Three identical convex lenses each of focal length f are placed in a straight line separated by a distance f from each other. An object is located in \(\frac{f}{2}\) in front of the leftmost lens. Then,

7.
If the velocity of light in vacuum is $3\times10^{8}\, ms^{-1},$ the time taken (in nanosecond) to travel through a glass plate of thickness $10 \,cm$ and refractive index $1.5$ is

9.
A ray of light is incident at an angle $i$ on a glass slab of refractive index $\mu$. The angle between reflected and refracted light is $90^{\circ}$. Then, the relationship between $i$ and $\mu$ is

10.
If \(\vec{n}_1\), \(\vec{n}_2\), and \(\vec{i}\) represent unit vectors along the incident ray, reflected ray, and normal to the surface, respectively, then:

12.
An object placed in front of a concave mirror at a distance of $x \,cm$ from the pole gives a $3$ times magnified real image. If it is moved to a distance of $(x+5)\, cm$, the magnification of the image becomes $2$. The focal length of the mirror is

13.
The intermediate image formed by the objective of a compound microscope is

14.
If the focal length of the eye-piece of a telescope is doubled, its magnifying power $(m)$ will be

15.
Two convex lenses (\(L_1\) and \(L_2\)) of equal focal length \(f\) are placed at a distance \(\frac{f}{2}\) apart. An object is placed at a distance \(4f\) to the left of \(L_1\) as shown in the figure. The final image is at:

Comments

SUBSCRIBE TO OUR NEWS LETTER

WBJEE PYQs for Ray optics and optical instruments with Solutions

1.A parallel beam of light is incident on a glass prism in the shape of a quarter cylinder of radius $R \,= \,0.05\, m$ and refractive index n = $1.5$ placed on a horizontal table as shown in the figure. Beyond the cylinder, a patch of light is found whose nearest distance $x$ from the cylinder is

2.There is a small air bubble at the center of a solid glass sphere of radius \(r\) and refractive index \(\mu\). What will be the apparent distance of the bubble from the centre of the sphere, when viewed from outside?

3.A biconvex lens of focal length $f$ and radii of curvature of both the surfaces $R$ is made of a material of refractive index $n_1$. This lens is placed in a liquid of refractive index $n_2$. Now this lens will behave like

4.A diver at a depth of $12\, m$ in water $\bigg(\mu = \frac{4}{3}\bigg)$ sees the sky in a cone of semi vertical angle

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

7.If the velocity of light in vacuum is $3\times10^{8}\, ms^{-1},$ the time taken (in nanosecond) to travel through a glass plate of thickness $10 \,cm$ and refractive index $1.5$ is

9.A ray of light is incident at an angle $i$ on a glass slab of refractive index $\mu$. The angle between reflected and refracted light is $90^{\circ}$. Then, the relationship between $i$ and $\mu$ is

10.If \(\vec{n}_1\), \(\vec{n}_2\), and \(\vec{i}\) represent unit vectors along the incident ray, reflected ray, and normal to the surface, respectively, then:

12.An object placed in front of a concave mirror at a distance of $x \,cm$ from the pole gives a $3$ times magnified real image. If it is moved to a distance of $(x+5)\, cm$, the magnification of the image becomes $2$. The focal length of the mirror is

13.The intermediate image formed by the objective of a compound microscope is

14.If the focal length of the eye-piece of a telescope is doubled, its magnifying power $(m)$ will be

15.Two convex lenses (\(L_1\) and \(L_2\)) of equal focal length \(f\) are placed at a distance \(\frac{f}{2}\) apart. An object is placed at a distance \(4f\) to the left of \(L_1\) as shown in the figure. The final image is at:

Comments

SUBSCRIBE TO OUR NEWS LETTER

1.
A parallel beam of light is incident on a glass prism in the shape of a quarter cylinder of radius $R \,= \,0.05\, m$ and refractive index n = $1.5$ placed on a horizontal table as shown in the figure. Beyond the cylinder, a patch of light is found whose nearest distance $x$ from the cylinder is

2.
There is a small air bubble at the center of a solid glass sphere of radius \(r\) and refractive index \(\mu\). What will be the apparent distance of the bubble from the centre of the sphere, when viewed from outside?

3.
A biconvex lens of focal length $f$ and radii of curvature of both the surfaces $R$ is made of a material of refractive index $n_1$. This lens is placed in a liquid of refractive index $n_2$. Now this lens will behave like

4.
A diver at a depth of $12\, m$ in water $\bigg(\mu = \frac{4}{3}\bigg)$ sees the sky in a cone of semi vertical angle

5.
Three identical convex lenses each of focal length f are placed in a straight line separated by a distance f from each other. An object is located in \(\frac{f}{2}\) in front of the leftmost lens. Then,

7.
If the velocity of light in vacuum is $3\times10^{8}\, ms^{-1},$ the time taken (in nanosecond) to travel through a glass plate of thickness $10 \,cm$ and refractive index $1.5$ is

9.
A ray of light is incident at an angle $i$ on a glass slab of refractive index $\mu$. The angle between reflected and refracted light is $90^{\circ}$. Then, the relationship between $i$ and $\mu$ is

10.
If \(\vec{n}_1\), \(\vec{n}_2\), and \(\vec{i}\) represent unit vectors along the incident ray, reflected ray, and normal to the surface, respectively, then:

12.
An object placed in front of a concave mirror at a distance of $x \,cm$ from the pole gives a $3$ times magnified real image. If it is moved to a distance of $(x+5)\, cm$, the magnification of the image becomes $2$. The focal length of the mirror is

13.
The intermediate image formed by the objective of a compound microscope is

14.
If the focal length of the eye-piece of a telescope is doubled, its magnifying power $(m)$ will be

15.
Two convex lenses (\(L_1\) and \(L_2\)) of equal focal length \(f\) are placed at a distance \(\frac{f}{2}\) apart. An object is placed at a distance \(4f\) to the left of \(L_1\) as shown in the figure. The final image is at: