JEE Main 2023 (Online) 11th April Evening Shift | Geometrical Optics Question 105 | Physics

The critical angle for a denser-rarer interface is $$45^{\circ}$$. The speed of light in rarer medium is $$3 \times 10^{8} \mathrm{~m} / \mathrm{s}$$. The speed of light in the denser medium is:

$$2 .12 \times 10^{8} \mathrm{~m} / \mathrm{s}$$

$$5 \times 10^{7} \mathrm{~m} / \mathrm{s}$$

$$\sqrt{2} \times 10^{8} \mathrm{~m} / \mathrm{s}$$

$$3.12 \times 10^{7} \mathrm{~m} / \mathrm{s}$$

JEE Main 2023 (Online) 10th April Morning Shift

MCQ (Single Correct Answer)

-1

An object is placed at a distance of 12 cm in front of a plane mirror. The virtual and erect image is formed by the mirror. Now the mirror is moved by 4 cm towards the stationary object. The distance by which the position of image would be shifted, will be

4 cm towards mirror

2 cm towards mirror

8 cm away from mirror

8 cm towards mirror

JEE Main 2023 (Online) 8th April Morning Shift

MCQ (Single Correct Answer)

-1

In a reflecting telescope, a secondary mirror is used to:

make chromatic aberration zero

remove spherical aberration

reduce the problem of mechanical support

move the eyepiece outside the telescopic tube