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A total solar eclipse happens when the Moon passes between the Earth and the Sun, blocking the Sun’s light. Because the Earth’s diameter is much larger than the Moon’s, the Moon’s shadow covers only a small area on Earth, so only people in the narrow “path of totality” see the Sun fully covered.

No expanded working has been attached for this question yet. The verified answer is Option C.

Cyan is a bluish-green colour

Lamps in lightenings are arranged to reduce the heat losses - resultant resistance is small for parallel arrangement which indicate low heat losses [Heat \(\alpha\) R]

u + v = 40 \(\frac{v}{u}\) = 3 v = 3u u + 3u = 40 4u = 40 u = 10cm v = 3u = 30cm f = \(\frac{uv}{u + v} = \frac{10(30)}{10 + 30} = \frac{300}{40}\) = 7.5 cm

- a ray of light passing through the centre of a curvature is returned along the same path - angle difference along the same path is zero

\(V = \frac{Distance}{time}\) = \(\frac{50cm}{2s}\) = 25 cms\(^{-1}\). \(V = f \lambda\) \(f = \frac{V}{\lambda}\) \(f = \frac{25}{5}\) = 5 Hz

- sound travels through solids, liquids & gases - sound travels faster in solid than in liquid & faster in liquid than in gases.

Mixing blue and red pigments in equal amount gives magenta when illuminated by white light

The image in a plane mirror is as far behind the mirror as the girl is in front of it. If she is at a distance d from the mirror, her image is also d behind it. Total distance between girl and image = 2d. v = \(\frac{\text{d}}{\text{t}}\) or v ∝ d d = x, v = 4m/s d = 2x, v = ? (girl & image) v = 2 x 4 = 8m/s.

f\(_1\) = f(v - v\(_o\)) v - v\(_s\) = 1200(340 - 15) 340 - 20 = 1.22KHz

Wave front is a line or section taken through an advancing wave in which the particles are in phase.

Depth of sea can be measured by echo, a reflected sound waves.

Dispersion is due to different refractive indices speeds and wavelengths.

Colours presented by objects are the ones reflected