1
JEE Main 2022 (Online) 26th July Morning Shift
+4
-1

In Young's double slit experiment, the fringe width is $$12 \mathrm{~mm}$$. If the entire arrangement is placed in water of refractive index $$\frac{4}{3}$$, then the fringe width becomes (in mm):

A
16
B
9
C
48
D
12
2
JEE Main 2022 (Online) 25th July Evening Shift
+4
-1

For an object placed at a distance 2.4 m from a lens, a sharp focused image is observed on a screen placed at a distance 12 cm from the lens. A glass plate of refractive index 1.5 and thickness 1 cm is introduced between lens and screen such that the glass plate plane faces parallel to the screen. By what distance should the object be shifted so that a sharp focused image is observed again on the screen?

A
0.8 m
B
3.2 m
C
1.2 m
D
5.6 m
3
JEE Main 2022 (Online) 25th July Morning Shift
+4
-1

Which of the following statement is correct?

A
In primary rainbow, observer sees red colour on the top and violet on the bottom
B
In primary rainbow, observer sees violet colour on the top and red on the bottom
C
In primary rainbow, light wave suffers total internal reflection twice before coming out of water drops.
D
Primary rainbow is less bright than secondary rainbow.
4
JEE Main 2022 (Online) 25th July Morning Shift
+4
-1

Time taken by light to travel in two different materials $$A$$ and $$B$$ of refractive indices $$\mu_{A}$$ and $$\mu_{B}$$ of same thickness is $$t_{1}$$ and $$t_{2}$$ respectively. If $$t_{2}-t_{1}=5 \times 10^{-10}$$ s and the ratio of $$\mu_{A}$$ to $$\mu_{B}$$ is $$1: 2$$. Then, the thickness of material, in meter is: (Given $$v_{\mathrm{A}}$$ and $$v_{\mathrm{B}}$$ are velocities of light in $$A$$ and $$B$$ materials respectively.)

A
$$5 \times 10^{-10} \,v_{\mathrm{A}}\, \mathrm{m}$$
B
$$5 \times 10^{-10} \mathrm{~m}$$
C
$$1.5 \times 10^{-10} \mathrm{~m}$$
D
$$5 \times 10^{-10} \,v_{\mathrm{B}} \,\mathrm{m}$$
JEE Main Subjects
Physics
Mechanics
Electricity
Optics
Modern Physics
Chemistry
Physical Chemistry
Inorganic Chemistry
Organic Chemistry
Mathematics
Algebra
Trigonometry
Coordinate Geometry
Calculus
EXAM MAP
Joint Entrance Examination