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(1)/v + (1)/u = (1)/f (1)/v + (1)/15 = (1)/5 (1)/v = (1)/5 - (1)/15 = (3 - 1)/15 = (2)/15 ∴ v = (15)/2 = 7.5 cm magnification = (v)/u = (image size)/object size (7.5)/15 = (X)/4 ∴ image size. X = (7.5 x 4)/15 = 2 cm

Refraction index, n = (real depth)/apparent depth 1.5 = (10)/X X = (10)/1.5 = 6.67 cm

Dispersion is the splitting of white light into its spectral component colors and is caused by different speed of the colors in the prism.

Sound wave requires a material medium for its propagation. so when air is being pumped out the density of the medium is being reduced and the sound dies down. when all the air has been pumped out of the glass, no sound will be heard, as sound sound cannot travel through vacuum

The lengthening effect of sound is known as reverberation.

The retina is light sensitive layer living the inner wall of the eye where image is formed. in the camera, image is formed on a light sensitive film.

Concave lens diverges parallel rays of light. A short sighted person has the image formed before the retina,and the rays have to be diverged so that they intersect to form image onto the retina

The Blood is a mixture which consists of water, proteins, fats, oil, sugar, vitamins, hormones, enzymes,e\ etc

When a cold milk bottle is taken out from the refrigerator, the water vapor in the air around the bottle comes in contact with the cold surface of the bottle and gets condensed.

Calcium trioxonitrate(V) is (CaNO\(_3\))\(_2\) The molecular mass of CaNO\(_3\))\(_2\) = 40 + (14 + (16 X 3)) x 2 = 164 Relative molecular mass of nitrogen(N\(_2\)) = 14 x 2 = 28 % by mass of nitrogen in CaNO\(_3\))\(_2\) = \(\frac{28}{164}\) x \(\frac{100}{1}\) = 17.073 ≈ 17.1%

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

Nitrogen has 7 electrons in all. Its electronic configuration is = \(1s^22s^22p^3\) So, it has three unpaired electrons in its p-orbitals. Note that the p orbital can accommodate a maximum of 6 electrons

The maximum number of electrons present in a particular shell is calculated by the formula 2n2, where “n” represents the shell number. For instance, K shell is the first shell and it can hold up to 2(1)2 = 2 electrons. Similarly, L shell is the second shell and it can hold up to 2(2)2 = 8 electrons.

Given: V\(_1\) = V cm\(^3\) P\(_1\) = P mmHg V\(_2\) = ? P\(_2\) = \(\frac{P}{2}\) At constant temperature ⇒ Boyle's Law P\(_1\)V\(_1\) = P\(_2\)V\(_2\) V\(_2\) = \(\frac{{P_1}{V_1}}{P_2}\) = \(\frac{{P}\times{V}\times {2}}{P}\) V\(_2\) = 2V

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