1
JEE Advanced 2022 Paper 1 Online
Numerical
+3
-0

A rod of length $2 \mathrm{~cm}$ makes an angle $\frac{2 \pi}{3} \mathrm{rad}$ with the principal axis of a thin convex lens. The lens has a focal length of $10 \mathrm{~cm}$ and is placed at a distance of $\frac{40}{3} \mathrm{~cm}$ from the object as shown in the figure. The height of the image is $\frac{30 \sqrt{3}}{13} \mathrm{~cm}$ and the angle made by it with respect to the principal axis is $\alpha$ rad. The value of $\alpha$ is $\frac{\pi}{n} r a d$, where $n$ is __________ .

2
JEE Advanced 2020 Paper 2 Offline
Numerical
+3
-1
A large square container with thin transparent vertical walls and filled with water (refractive index $${4 \over 3}$$) is kept on a horizontal table. A student holds a thin straight wire vertically inside the water 12 cm from one of its corners, as shown schematically in the figure. Looking at the wire from this corner, another student sees two images of the wire, located symmetrically on each side of the line of sight as shown. The separation (in cm) between these images is ;

3
JEE Advanced 2019 Paper 2 Offline
Numerical
+3
-0
A monochromatic light is incident from air on a refracting surface of a prism of angle 75$$^\circ$$ and refractive index $${n_0} = \sqrt 3$$. The other refracting surface of the prism is coated by a thin film of material of refractive index n as shown in figure. The light suffers total internal reflection at the coated prism surface for an incidence angle of $$\theta \le 60^\circ$$. The value of n2 is .............
4
JEE Advanced 2019 Paper 1 Offline
Numerical
+3
-0
A planar structure of length L and width W is made of two different optical media of refractive indices n1 = 1.5 and n2 = 1.44 as shown in figure. If L >> W, a ray entering from end AB will emerge from end CD. CD only if the total internal reflection condition is met inside the structure. For L = 9.6 m, if the incident angle $$\theta$$ is varied, the maximum time taken by a ray to exit the plane CD is t $$\times$$ 10-9 s, where, t is ................

[Speed of light, c = 3 $$\times$$ 108 m/s]