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For the transformer, V ∝ ∩ => V s ∝ ∩s; Vp ∝ ∩p => \(\frac{V_p}{V_s} = \frac{∩_p}{∩_s}\), therefore \(\frac{120}{1200} = \frac{∩_p}{1000}\) therefore ∩\(_p \times 1200 = 120\times 1000\) ∩\(_p = 120\times\frac{1000}{1200}\) = 100

D = Lead: Lead is highly effective at shielding against ionizing radiation, particularly gamma rays, due to its high density and atomic number.

The sun produces energy primarily through the nuclear fusion of hydrogen nuclei, a reaction that occurs at extremely high temperatures, around 10\(^7\) K. H\(_1\) + H\(_1\) → \(_2\)H

The force on a current carrying conductor in a magnetic field is greatest when the conductor lies perpendicular in the magnetic field

Eddy currents are loops of electric current induced in conductors by a changing magnetic field, leading to energy losses as heat. Using insulated soft iron wires helps minimize these losses by reducing electrical conductivity and preventing the flow of these currents through insulation.

The magnetic force on a charge is given by F = qVB Sinθ, thus the force is proportional to both the magnitude by the charge (q) and the velocity (V) (i/e F α qV)

Since the number of pulleys present is 6, it implies that the velocity ratio V.R = 6 Efficiency = \(\frac{\text{M.A}}{\text{V.R}}\times \frac{100}{1}\) = \(\frac{Load}{Effort}\times\frac{1}{V.R}\times\frac{100}{1}\) = \(\frac{240}{80} \times\frac{1}{6} \times\frac{100}{1}\) = 50% ∴ Efficiency = 50%

Energy = 1/2CV2 ∴Energy of P = 1/2 x 2 x V2 = V2 Energy of Q = 1/2 x 4 x V2 = 2V2 ∴ P/Q = V2/2V2 = 1/2 => P:Q = 1:2

The molecular theory of matter explains processes like evaporation, thermal conduction, and convection, but it does not account for heat radiation, which involves energy transfer through electromagnetic waves and does not require a medium.

Pressure = \(\frac{\text{Force}}{\text{cross-sectional area}}\) From the equation above Option A is incorrect: increases with an increase in surface area

Upthrust = 96 - 32 = 64N mass(m) = \(\frac{64}{10} = 6.4 kg\) volume = \(\frac{mass}{Density} = \frac{6.4}{1000}\) = 6.4 x 10-3m3

Given that: Weight of the block: 15N Horizontal force applied: 3N Since the applied force (3 N) is less than the maximum static friction (which can be greater than or equal to the weight of the block), the friction force will match the applied force to prevent motion Therefore, The friction force on the block is: 3N

For a body moving at a constant speed, the distance x traveled can be represented by the equation: x = U t (constant speed = zero acceleration)

The amplitude of the motion of a body performing simple harmonic motion (SHM) decreases over time primarily due to energy loss, often caused by friction or other resistive forces. Therefore OPTION A is correct.

amax = \(\omega^2 r = 10^2 \times \frac{5}{100} = 5ms^{-2}\)