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Power = \(\frac{w}{t}\) Given: F = 50N, s = 500cm → 5m and t = 1s W = f x s = 50 x 5 = 250J Power = \(\frac{250}{1}\) = 250W

Convection: The movement of air due to temperature differences between land and water, leading to the formation of breezes.

At equilibrium, the pressures at the bottom of both columns are equal: ρ\(_m\) \times h\(_m\) \times g = ρ\(_x\) \times h\(_x\) \times g g cancels out, so: ρ\(_m\) \times h\(_m\) = ρ\(_x\) \times h\(_x\) \(\rho_x = \rho_m \times \frac{h_m}{h_x} = 800 \times \frac{7.1}{14.2}\) \(\frac{7.1}{14.2} = 0.5\) \(\rho_x = 800 \times 0.5 = 400 \, \text{kg/m³}\) Relative density of X (with respect to methanol) = \(\frac{\rho_x}{\rho_m} = \frac{400}{800} = \mathbf{0.5}\)

An electroscope is a passive device used to detect and measure charges, not to produce or generate electric charge in a body.

When a galvanometer is connected to a shunt resistor, it is converted into an ammeter. By connecting a shunt in parallel with a galvanometer, it can measure larger currents without getting damaged, turning it into an ammeter

The distance to the wall is 408m, so the total distance (D) traveled by the sound is: D = 2 \times 408m = 816m But v = \(\frac{d}{t}\) = \(\frac{816}{2.4}\) = 340m/s

The elliptical shape of the Earth: The Earth is not a perfect sphere; it is slightly flattened at the poles and bulging at the equator. This shape causes variations in gravitational acceleration.

Dry Leclanché: This is a common non-rechargeable cell.

The question can be explained by Graham's law of diffusion. According to this law, under the same conditions of temperature and pressure, the rate of diffusion of a gas is inversely proportional to the square root of its molar mass. \(\frac{R_x}{R_y}\) = \(\sqrt{\frac{M_y}{M_x}}\) From the question, Gas X diffuses twice as fast as gas Y i.e x = 2y This implies x =2 while y = 1 From \(\frac{R_x}{R_y}\) = \(\sqrt{\frac{M_y}{M_x}}\) \(\frac{2}{1}\) = \(\sqrt{\frac{M_y}{M_x}}\) \(\frac{4}{1}\) = \(\frac{M_y}{M_x}\) M\(_y\) = 4 M\(_x\) ⇒ Gas Y is 4 times as heavy as Gas X. - Option B

To find the number of molecules, we'll use the formula: Number of moles = \(\frac{Number of molecules}{Avogadro number}\) But We were only given the mass of Helium = 11.5g , knowing the atomic mass or molar mass of He = 4 g/mol Number of moles = \(\frac{mass}{molar mass}\) = \(\frac{11.5}{4}\) = 2.875 moles Number of molecules = Number of moles x Avogadro number = 2.875 x 6.02 x 10\(^{23}\) = 17.3075 x 10\(^{23}\) = 1.73 x 10\(^{24}\)

Alnico is ferromagnetic, meaning it can be used to make permanent magnets. Alnico is an iron alloy with the acronym "al-ni-co" that's made up of aluminum (Al), nickel (Ni), and cobalt (Co). Option B

Gold and silver are noble metals, because they are resistant to corrosion and oxidation, even at high temperatures. Noble metals are a group of metals that are less reactive than other metals and are not easily corroded or oxidized.

Aluminum is extracted from bauxite by electrolysis. The extraction proceeds in two stages; 1. Purification of the Bauxite: The impure bauxite is heated with sodium hydroxide solution to form soluble sodium tetrahydroxy aluminate (iii). The impurities in the ore which are iron (iii) oxide and trioxosilicate (iv) compounds are not soluble in the alkali. They are therefore filtered off as a sludge. Aluminum hydroxide crystals is then added to filtrate, NaAl(OH)\(_4\) solution to induce the precipitation of Aluminum hydroxide. 2. The electrolysis of the pure alumina

In contact with water, calcium carbide instantly decomposes hydrolytically, yielding acetylene gas and calcium hydroxide. Calcium ethynide is also known as calcium carbide. CaC\(_2\) + 2H\(_2\)O → Ca(OH)\(_2\) + C\(_2\)H\(_2\)

Bitumen is the petroleum product which is used for surfacing roads. It is also known as asphalt. It is used as an alternative for coal-tar.​