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

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

If two cells of equal emf s are connected in parallel then the effective emf is equal to the emf of any one of the cells.

Is independent of the relative velocity of the layers is not true because: Viscosity is dependent on the relative velocity of the layers in a fluid; it describes how the fluid flows when layers move relative to each other. Viscosity depends on the area of the surface in contact Viscosity is independent of normal reaction Viscosity depends on the relative velocity between layers

Calculation of the force needed to produce extension of material F = Ke = 988.3 x 3 x 3 = 8840.74N

(a) Function of metal flat plate of solar panel - Receives and absorbs solar radiation to produce heat (b) Function of internal insulator of solar panel - Minimises heat loss (c) Function of tubes of solar panel - Helps to circulate the heat

(a) Type of material most suitable for the design of the core of an optical fibre - Glass/plasties (b) Condition necessary confine signal to the core of an optical fibre - The refractive index of the core must be greater than that of the cladding,

Expression for v c = kT\(^a\)U\(^b\), k is dimensionless [v] = k[T]\(^a\)[\(\mu\)]\(^b\) Lt\(^{-1}\) = kM\(^{a \div b}\) L\(^{a + b}\) T\(^{-2a}\) For T, -1 = 2a a = \(\frac{1}{2}\) For M, 0 = a + b b = -a = \(\frac{1}{2}\) v = KT\(^{\frac{1}{2}}\)\(\mu^{- \frac{1}{2}}\) OR v = k\(\sqrt{\frac{T}{\mu}}\)

To show that V\(_E\) = \(\sqrt{20R}\) KE = Gravitational Potential Energy \(\frac{1}{2}\)MV\(_E^2\) = \(\frac{GmM}{R}\) V\(_E^2\) = \(\frac{2GM}{R}\) but GM = gR\(^2\) V\(_E^2\) = \(\frac{2gR^2}{R}\) = 2gR V\(_E^2\) = \(\sqrt{2 \times 10 \times R}\) = \(\sqrt{20R}\) OR P.E = K.E mgR = \(\frac{1}{2}\)mv\(^2\) v\(^2\) = 2gR v = \(\sqrt{2gR}\) = \(\sqrt{20R}\)

Calculation of velocity of fired bullet Time of flight T = \(\frac{2u sin \theta}{g}\) 25 = \(\frac{2u sin 30}{g}\) u = 250ms\(^{-1}\)

- Travels a very long distance without losing its intensity - Has a very narrow optical bandwidth. - Gives more intense light/power - Is monochromatic

(a)i) Definition of a torque - The turning effect of force about an axis/pivot (ii) Factors that determine a torque - perpendicular distance of the force from the pivot - direction of the force. - magnitude of the force (b)(i) Definition of free fall: - The vertical motion of a body only under the influence of gravity/its own weight (ii) Calculation of the time taken by a body thrown vertically upward to reach the ground S = 10t - \(\frac{1}{2}\)10t\(^2\) -40 = 10t - \(\frac{1}{2}\)10t\(^2\) x 10 t\(^2\) (t + 2)(t - 4) = 0 Time to fall to the ground, t = 4s (c) Calculation of the mass of wood: - Mass of wood = upthrust due to water displace + upthrust due to oil displaced = 1000 x 2 x 8 x 8 x 10 + 720 x 6 x 8 x 8 x 10 = 0.404kg

(a)i) Explanation of resonance frequency as applied to RLC series circuit - It is the frequency of oscillation of an RLC series circuit when the capacitive reactance is equal to the inductive reactance. The impedance is equal to the resistance /the impedance is minimum. (ii) A sketched graph (iii) \(\alpha\) Relationship between current and voltage when f = f\(_o\); Current is in phase with the supply voltage (\(\beta\)) - Relationship when current and voltage when f = f\(_o\); Current lags the Supply voltage (\(\gamma\)) - Relationship between current and voltage when f > f\(_o\); Current leads the supply voltage. (b) (i) Definition of mutual inductance: The ratio of the induced emf in one coil/circuit to the time rate of change of current in the other coil. OR The production of e.m.f in a circuit as a result of the change in the magnetic flux/magnetic circuit in an adjacent circuit linked to it . (ii) Calculation of angular speed of the coil of an electric generator: E = \(\omega\)BAN 480 = \(\omega\) x 0.25 x \(\pi\) x (\(\frac{8.0 \times 10^{-2}}{2}\)) x 500 = \(\omega\) = 763.8 rad/s (c)(i) Explanation of eddy current: The current is induced and flows within a metal block when there is a change in magnetic flux linking the block. OR Loops of electric current induced within a conductor by the changing magnetic flux/field in the conductor. OR The localised electric current/loops of electric current (ii) Practical Uses of eddy current: - induction furnaces - induction coils - speedometers - induction meters

(a) (i) The angle of incidence in the optically denser medium for which the angle of refraction in the less dense medium is 90\(^o\) (ii) Conditions necessary for total internal reflection to occur: - Light rays must travel from a dense medium to a less dense medium. - Angle of incidence in the dense medium must be greater than the critical angle. iii) Practical applications of total internal reflection - Prism periscopes. - Prism Binoculars. - Fibre optics - Fish eye view. - Transmission of radio signals (b) Effects of refraction - straight objects placed in liquid appear bent (on the interface or boundary) - mirages. - dispersion of white light/formation of rainbow. - apparent displacement of objects placed in liquids/apparent shadows of pools base. (c)(i) Definition of progressive waves: A disturbance which travels through a medium that enables energy to be transferred from its source to another (without the particles of the medium transferred). OR Transfer of energy and momentum from the source of disturbances. (ii) (\(\alpha\)) calculation of frequency of wave y = 0.5 sin (1000) \(\pi\) t - 100 \(\pi \frac{x}{17}\) = a sin (2\(\pi ft - 2 \pi \frac{x}{\gamma}\)) = 2\(\pi f = 1000 \pi\) f = 500Hz (\(\beta\)) calculation of wavelength of wave \(\frac{2\pi}{\lambda} = \frac{100\pi}{17}\) \(\lambda\) = \(\frac{2 \times 17}{100}\) = 0.34m (\(\gamma\) calculation of speed of wave) v = f\(\lambda\) = 500 x 0.34 170ms\(^{-1}\)

(a)(i) Time/s 0 100 200 300 400 Reading on balance/g 203.22 201.62 199.79 198.26 196.50 Mass of water evaporated/g 0 1.60 (\(\frac{1}{2}\)) 3.43 (\(\frac{1}{2}\)) 4.96 (\(\frac{1}{2}\)) 6.72 (\(\frac{1}{2}\)) Energy supplied by heated/J 0 3800 (\(\frac{1}{2}\)) 7600 (\(\frac{1}{2}\)) 11400 (\(\frac{1}{2}\)) 15200 (\(\frac{1}{2}\)) (iv) Determination of slope of graph Slope = \(\frac{\Delta Q}{\Delta M}\) = \(\frac{14.0 - 2.0) \times 10^3}{6.1 - 0.8}\) = 2.26 x 10\(^3\)J/g (v) Meaning of the value of the slope of graph 2.26 x 10\(^2\)J of heat energy is needed to evaporate 1g of water at constant temperature. (b)(i) Explanation of saturated vapour pressure; At any given temperature, some energetic molecules of a liquid in a given system escape from the liquid surface as vapour and at the same time some return to the liquid. Vapour pressure is built up above the liquid in the process. When the rate of escape equals the rate of return, the vapour is said to be saturated and the pressure it exerts is called saturated vapour pressure at that temperature. (ii) Factor that affects saturated vapour pressure; - Temperature