Question Library

Annular Eclipse: Occurs when the Sun, Moon, and Earth are aligned in a straight line, but the Moon is at a distance where it does not completely cover the Sun.

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

The distance between two successive troughs of a wave is equal to one wavelength (\lambda) One wavelength (\lambda) is defined as the distance between two successive points in the same phase (crest to crest or trough to trough).

The speed of sound in air at a constant temperature is primarily dependent on the temperature of the air rather than the pressure. At a constant temperature, changes in pressure do not significantly affect the speed of sound.

Speed of sound = 60 m/s Time delay = 4 s (light travel time is negligible) Distance = speed \times time = 60 \times 4 = 240 m

Short-sightedness (myopia) means distant objects focus in front of the retina, with the far point at 95 cm. A diverging lens (concave) corrects this by creating a virtual image of distant objects (u = \infty) at the far point (v = -95 cm). Using the lens formula: 1/f = 1/v - 1/u = -1/95 - 0, so f = -95 cm (diverging lens with focal length 95 cm).

B. Ciliary muscle. The ciliary muscles control the shape of the lens, allowing the eye to focus on objects at different distances by changing the focal length of the lens.

The tension \( T \) in a string is defined as the force acting along the string. The dimensional formula for force is given by: \([T] = [F] = [M^1 L^1 T^{-2}]\) Thus, the dimensional symbol of tension in a string is: \([T] = [M L T^{-2}]\)

From Faraday's first law, the mass deposited \( m = Z Q \), where \( Z \) is the electrochemical equivalent and \( Q \) is the charge passed. Since the same charge \( Q \) passes through both voltmeters: \(Q = \frac{m_{\mathrm{Cu}}}{Z_{\mathrm{Cu}}} = \frac{m_{\mathrm{Ag}}}{Z_{\mathrm{Ag}}} \) Rearranging for \( Z_{\mathrm{Ag}} \): \(Z_{\mathrm{Ag}} = \frac{m_{\mathrm{Ag}} \cdot Z_{\mathrm{Cu}}}{m_{\mathrm{Cu}}} \) But: \( m_{\mathrm{Cu}} = 0.2 \, \mathrm{g} \), \( m_{\mathrm{Ag}} = 1.2 \, \mathrm{g} \), \( Z_{\mathrm{Cu}} = 0.00028 \, \mathrm{g \, C^{-1}} \) \(Z_{\mathrm{Ag}} = \frac{1.2 \times 0.00028}{0.2} = \frac{0.000336}{0.2} = 0.00168 \, \mathrm{g \, C^{-1}} \)

Magnesium (Mg) belongs to Group 2 (the Alkaline Earth metals) and Period 3 of the periodic table, meaning it has 2 valence electrons and three electron shells, placing it in the s-block.

The compound [Cu(NH\(_3\))\(_4\)]Cl\(_2\) is an ionic compound composed of a complex cation, the tetraamminecopper(II) ion ([Cu(NH\(_3\))\(_4\)]\(^{2+}\)), and two chloride anions (Cl\(^−\)). The primary force connecting the positively charged complex ion and the negatively charged chloride ions is the electrostatic attraction known as an ionic bond. This bond forms between species with a significant difference in electronegativity, specifically between a cation and an anion. Dative bonds (coordinate covalent bonds) exist within the complex ion itself, specifically between the central copper(II) ion and the nitrogen atoms of the ammonia ligands. Van der Waals forces and typical covalent bonds are not the main attractive forces between the distinct cation and anion units in this solid salt structure. The correct answer is ionic - option C