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Answer: B. I only (I true; II false, yellow deviated less than green; III false, rainbows from light refraction in drops.)

Answer: A n = \(\frac{1}{\text{sinC}}\) = \(\frac{1}{sin45º}\) = \(\sqrt{2}\).

\(_ag_g\) = \(\frac{\text{sini}}{\text{sinr}}\) sinr = \(\frac{\text{sini}}{_ag_g}\) sinr = \(\frac{0.5}{1.5}\) sinr = 0.3

A. Red Red light has the longest wavelength and the lowest frequency compared to the other colors listed. ROYGBIV: arranged in increasing frequency or decreasing wavelength.

For a ray entering and exiting parallel faces of a glass slab, the refractive index is given by: n = \(\frac{\text{real depth}}{\text{apparent depth}}\) Where SR = 6cm is apparent depth, SQ = 10cm real depth. n = \(\frac{10}{6}\) = 1.6666 ≈ 1.67

i at m\(_1\) = 60^\circ → r = 60^\circ at m\(_1\) (law of reflection i ^\circ = r ^\circ) i at m\(_2\) = 30^\circ i = r, ∴ r = 30^\circ

\(\lambda\) = \(\frac{\text{Sin i}}{\text{Sin r}}\) = \(\frac{Sin 60º}{Sin 32º}\) = 1.63

For all positions of the object formed by a concave (diverging) lens, the image is virtual, erect, and diminished.

2a. Table of observations D(cm) D\(^2\)(cm\^2\) X\(_1\)(cm) L = (X\(_1 - X_2\)) L\(^2\)(cm\(^2\)) 100 10000 80.50 62.20 3868.8 90 8100 70.20 51.20 2621.4 80 6400 59.10 39.10 1528.8 70 4900 46.70 24.70 610.09 60 3600 29.00 21.40 457.96 S = \(\frac{y_2 - y_1}{x_2 - x_1}\) = \(\frac{6250 - 3250}{100 - 60}\) = \(\frac{3000}{40}\) = 75 K = \(\frac{\text{s}}{4}\) = \(\frac{75}{4}\) = 18.75 Precautions: (i) I carefully avoided parallax error by ensuring my eyes were directly in line with the markings on the metre rule while taking measurements to improve accuracy. (ii) I adjusted the setup and focused precisely to ensure a sharp and well-defined image was formed on the screen, minimizing errors due to blurriness or misalignment. (iii) I made sure that the experimental apparatus was stable and free from vibrations to avoid any disturbance during measurements. (iv) I ensured that the metre rule was properly calibrated and positioned perpendicular to the setup to prevent measurement inaccuracies due to angle errors. bi. A real image is formed when light rays converge and meet at a point, allowing it to be projected onto a screen. It is typically inverted relative to the object, as seen in concave mirrors or convex lenses when the object is beyond the focal point. On the other hand, a virtual image is formed when light rays appear to diverge from a point but do not actually meet. This type of image cannot be projected onto a screen and is always upright, as seen in plane mirrors or convex mirrors. bii. See diagram above.

Refractive index = \(\frac{\text{real depth}}{\text{apparent depth}}\) Real depth = refractive index x apparent depth Apparent depth = 10cm Refractive index = 1.33 Real depth = 1.33 x 10 = 13.3cm.

When light travels from a less dense medium (like air) to a denser medium (like glass or water), its speed decreases due to the higher optical density of the new medium. The frequency of light remains constant when it passes from one medium to another. Although the speed changes, the frequency is determined by the source of the light and does not change with the medium.

Chromatic aberration occurs because different wavelengths of light are refracted by different amounts when passing through a lens. Chromatic aberration can be corrected by using a combination of diverging (concave) and converging (convex) lenses, which help focus different colors of light to the same point.

Twice the focal length of the lens: this is because, for a real image to be formed, the object must be placed outside the focal length of the lens, typically at a distance greater than twice the focal length.

Diameter = 20cm The radius of curvature, R = 10cm But, focal length, f = \(\frac{R}{2} = \frac{10}{2}\) = 5 cm. Because the inside portion is polished, light reflects off the hollow, caved-in interior. A mirror that reflects light from its inner surface is concave.

The formation of a rainbow is primarily due to dispersion, as it involves the separation of light into its constituent colors when it passes through water droplets in the atmosphere, it is refracted and dispersed due to varying wavelengths.