Chapter Test: Ray Optics and Optical Instruments - 2 JEE Physics Free MCQs

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D is correct.

Let n_air = 1 and n_rod = 2/√3. By Snell's law at the flat end, sin r = sin θ / n,

where r is the angle of the refracted ray inside the rod measured from the axis.

For the ray to graze the inner curved wall the incidence at the curved surface must equal the critical angle.

The critical angle is θ_c = sin^-1(1/n). For n = 2/√3, we have 1/n = √3/2, so θ_c = 60°.

In the meridional plane (plane containing the axis and the ray) the normal to the cylindrical surface is perpendicular to the axis, so the angle between the ray and the normal at the curved surface is 90° - r.

Setting this equal to the critical angle gives 90° - r = 60°, hence r = 30°.

Now use Snell's law:

sin r = sin θ / n

⇒ sin θ = n·sin r = (2/√3)·sin 30°

= (2/√3)·(1/2) = 1/√3.

Therefore θ = sin^-1(1/√3), which is option D.

Hence there are 6 minimas of y-axis and 5 maxima of x-axis.

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When a light wave is reflected from an object , it changes not only it's amplitude but also its phase according to the properties of the object at a particular point. 
Therefore, option A is the right answer.

The images of clouds and trees in water are always less bright than in reality because only a portion of the incident light is reflected and quite a large portion goes mid water.

 As per the question, rays are falling on the mirror, which cleared that Regular reflection is taking place.
So, As per the laws of regular reflection.
=> ∠incident= ∠reflection
∠incident= ∠reflection=38A^o
Also we know that normal is at 90°to the mirror.
Now, to get the required angle we need to reduce angle of reflection from normal.
=>90A^o-38A^o=52A^o
so, the correct answer is option B.

If the final rays are converging, we have a real image.
This is because a real image is formed by converging reflected/refracted rays from a mirror/lens.
The correct answer is option B.

Lateral inversion-The phenomenon of left side appearing right side and right side appearing left side on reflection in a plane mirror is called lateral inversion.
Letters that do not show lateral inversion are,
A, H, I, M, O, T, U, V, W, X, Y
Hence, HOX will not show lateral inversion.