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

The horizontal component of velocity, \(V_{x}\), is unaffected by the acceleration of free fall and remains constant. \(V_{x} = U_{x} = Ucos\theta\) = \(15 \times cos45 = 15\times 0.7071\) \(\approxeq 10.6ms^{-1}\)

The rate of evaporation is increased by the lowering of atmospheric pressure and not its increase. Every other factor stands, for the increase of evaporation process.

Let \(h_{Q}\) and \(\rho_{Q}\) be the least length and the density of \(Q_{1}\) while \(h\) and \(\rho\) are the length and density of mercury respectively. \(h\times \rho \times g = h_{Q} \times \rho_{Q} \times g\) \(76cm \times 13.6 \times 10 = h_{Q} \times 16.2 \times 10\) \(h_{Q} = \frac{76\times13.6\times10}{16.2\times10}\) \(h_{Q} = \frac{10336}{162}\) \(h_{Q} \approxeq 63.8cm = 638mm\)

The gamma rays have the shortest wavelength and therefore, impart the highest photon energy.

Upward force = downward force = weight of the Bar 20N + 20N = Weight of the BAR Therefore, the weight of the bar = 40N

\(F= \frac{Gm_{1}m_{2}}{r^{2}}\) \(m_{1} = 100kg\) \(m_{2} = 20kg; r =1.2m\) \(G= 6.67\times 10^{-11}\) \(F = \frac{6.67\times 10^{-11}\times 100\times 20}{(1.2)^{2}} = 9.26\times 10^{-8}\) Gravitational force is always attractive. Therefore, the net force acting on object Q will pull it directly towards the larger mass, P.

The ideal transformer (either step-up or step-down) works with the equation: \(\frac{V_{s}}{V_{p}} = \frac{N_{s}}{N_{p}} = \frac{I_{p}}{I_{s}}\) where \(V_{s}\) and \(V_{p}\) are the voltages applied to the secondary and the primary respectively \(N_{s}\) and \(N_{p}\) are the number of turns on the secondary and primary coils respectively \(I_{p}\) and \(I_{s}\) are the currents flowing in the primary and secondary coils respectively. \(\frac{V_{s}}{100} = \frac{200}{100}\) \(V_{s} = \frac{200\times 100}{100} = 200V\)

The velocity ratio and therefore, the mechanical advantage of an inclined plane system increases as \(\theta\) decreases and vice-versa.

Given \(K_{1}\) = \(\frac{mv^{2}}{2}\). When v is halved, we have \(K_{2}\) = \(\frac{m\times (\frac{v}{2})^{2}}{2}\) = \(\frac{K_{1}}{4}\) Hence, the initial kinetic energy is quartered.

Capacitors pass AC but block DC signals (when charged up to the applied DC voltage), they are often used to separate the AC and DC components of a signal. Capacitors are also primarily used to store energy.

Two magnetic lines of force can not intersect each other.

(a) Uniform acceleration is the constant time rate of increase in velocity. (b) (i) Horizontal Force; Forward force - Thrust backward force - Frictional force (ii) Vertical Force Upward force - Normal reaction. Downward force - Weight of the car. (c) SEE THE DIAGRAM ABOVE. (ii) (\(\lambda\)) Total distance = Area of trapezium OABC = \(\frac{1}{2}\)[AB + OC] AD = \(\frac{1}{2}\)[60+30] x 25 =1125m (\(\beta\)) Deceleration = slope of BC = \(\frac{BE}{CE} = \frac{25}{10}\) = 25m/s\(^2\) (d) Work done = \(\frac{1}{2}\)Fe = \(\frac{1}{2}\) x 12 x \(\frac{0.5}{100}\)J = 0.03J

(a) (i) Radiation: Surface area, Temperature. (ii) Convection: Nature, Density/Viscosity of the fluid, Thermal conductivity of fluid, Specific heat capacity of fluid and Exposed surface area. (b) Factors that determine the quantity of heat in a body: Heat/thermal capacity and. Temperature (c) It means that 2.72 x 105J of heat energy is required/ needed to change I kg of mercury at its boiling point to vapour (without temperature change) (d) (i) heat supplied by heater = ivt = \(\frac{v^2}{R}\)t heat gained by water = M\(_w\)C\(_w\)(\(\theta_2\) - \(\theta_1\)) where M\(_w\) = mass of water C\(_w\) = s.h.c of water \(\theta_2\) = final temp. of water \(\theta_1\) = initial temp. of water Heat gained by jug = C\(_j\) (\(\theta_2\) - \(\theta_1\)) \(\frac{v^2t}{R}\) = M\(_w\)C\(_w\) (\(\theta_2\) - \(\theta_1\)) = \(\frac{220^2 \times 4 \times 60}{35}\) = M\(_w\) x 4200[100 - 28] + 250[100 - 28] M\(_w\) = 1.038kg

(a)(i) Reactance is the opposition to the flow of a.c offered by a capacitor or an inductor or both. (ii) Impedance is the overall opposition of a mixed circuit containing a resistor, an inductor and/or a capacitor. (b) (i) Emf is induced because the coil rotates at a steady speed about a fixed axis in the magnetic field of the elctromagnet, it cuts through the magnetic lines of force. (ii) The direction of current is reversed in each half of the rotation of the coil. (iii) The law used to determine the direction of the induced current is Lenz's law. It states that the direction of the induced current is such as to oppose the change producing it. (iv) The induced e.m.f can be increased by any two of the following: increased speed of rotation, efficient core design, increased number of turns in the coil and increased area of coil. (c) E = Power x Time = 6 x 5 x 60 =1800J