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In plane polarisation of light, the vibrations are made to vibrate only in one plane perpendicular to the direction of the light. It is used in polaroids.

H = \(\frac{1}{2} gt^2\) S = ut t = \(\frac{5}{u} = \frac{20}{5} = 45\) H = \(\frac{1}{2}gt^2 = \frac{1}{2} \times 10 x 4^2\) = 80m

Mass deposited = 21t I = \(\frac{m}{2t} = \frac{0.66}{33 \times 10^{-5} \times 30 \times 60}\) = 1.11A error = 1.11 - 1 = 0.11A

(a) Surface tension is the force per unit length acting at right angle to one of a line drawn in the surface. (b) By adding detergents, soap or oil. By heating the liquid.

(a) Young's Modulus is the ratio of tensile stress to tensile strain (b) Length of wire, extension of wire, load used, diameter of wire.

(a) Electrical discharge through low pressure gas (b) - Nature of the gas in the tube - Nature of the coating d inside the tube.

(a) \(_gamma\) - rays. X - rays, radio waves, infra-red. - To determine the concentration of sugar solution - In polaroids used in sun glasses to reduce the intensity of incident sunlight glare from reflecting surfaces.

(a) Hooke's law states that the force applied on an elastic materal is proportional to its extension, provided the elastic limit is not exceeded (b) R.D = \(\frac{\text{weight in air}}{\text{upthrust}} = \frac{10}{10.5 - 6.8} = \frac{10.5}{3.7} = 2.84\)

(a) This is the process by which a solution or a molten substance is broken down into the component parts by the passage of an electric current through it. (b) \(\frac{Electrolytes}{\text{salt solution}}\) = \(\frac{\text{non - electrolytes}}{\text{Sugar solution}}\) grape fruit juice paraffin

(a) Heinsenberg's uncertainty principle states that it is impossible to determine simultaneously the exact position and exact momentum of a particle (b) Black body radiation - Photo electricity.

(a) - Sum of forces in one direction is equal to the sum of forces in opposite direction. - Sum of anti-clockwise moments about a point is equal to the sum of clockwise moment about the same point. (b) Diagram: Method: Suspend the metre rule on a knife edge. Adjust its position until it balances horizontally. Note the balance point G. Then suspend a mass M on one side of the rule. Adjust the rule until it balances horizontally again. Read and record X and Y as in the diagram above. According to the principle of moment: Mgx = Mgy m = \(\frac{Mgy}{gx} = \frac{My}{x}\) m = mass of rule Precautions - Avoid drought - Avoid parallax in reading the metre rile (c)(i) Deceleration a = \(\frac{u - v}{t} = \frac{20 - 0}{0.1}\) = 200ms Resistance = ma = 0.12 x 200 = 24N (ii) Distance, s \(\frac{u^2 - v^2}{2a} = \frac{20^2 - O^2}{2 \times 200} = \frac{400}{400}\) = 1.0m

(a)(i) Work is the product of force and distance moved in the direction of the force (ii) Power is the time rate of doing work. Unit of power is watts or J / sec. (b) E = \(\frac{\text{Work output}}{\text{work input}}\) x 100% work input E = \(\frac{\text{load x distance moved by load}}{\text{effort x distance moved by effort}}\) But Ma = \(\frac{Load}{effort}\) and V.R = \(\frac{\text{distance moved by effort}}{\text{Effort distance moved by load}}\) E = \(\frac{MA}{1} \times \frac{1}{VR}\) x 100% E = \(\frac{MA}{V.R}\) x 100% (c)(i) VR = \(\frac{1}{sin \theta}\) = \(\frac{1}{sin 45^o} = \frac{1}{0.2588}\) = 3.86 75% = \(\frac{9000}{Win}\) x 100% Win = \(\frac{9000 \times 100}{75}\) = 12,000J work input = 12000 J. (d) At constant pressure, the number of collision per unit time is constant. An increase in temperature causes average Kinetic energy increases. The molecules then move faster. The volume therefore increases so as to maintain the number of collision per unit time.

(a) Reflection, refraction, polarisation = 3.86 9000 Win (b)(i) Method: Keep the distance AB constant and tight. Sound fork of known frequency F and pluck the string in the middle. Then add load to scale pan until resonance occurs. Record the load in the scale pan and the corresponding frequency. Repeat the experiment for about four tuning forks of known frequencies. Graph: Plot a graph of frequency, F against the square root of the load. Observation: The straight line graph passing through the origin shows that frequency is proportional to the square root of tension (load). F \(\alpha\) T Precautions: - Sonometer wire is firmly fixed. - Strike the tuning fork on a pad (c)

(a) (b) The sensitivity is increased by a weak spring and increasing the strength of the magnet C (c)(i) (ii) X = \(\frac{1}{2 \pi FC} = \frac{1}{2 \pi \frac{160}{\pi} \times 4}\) = 781\(\Omega\) (iii) X\(_L\) = 2\(\pi\)fL = 2\(pi\) x \(\frac{160}{\pi}\) x 3 = 960\(\Omega\) (iv) Z = \(\sqrt{R^2 + (X_L - X_c)^2} = \sqrt{100^2 + (960 - 781)^2}\) = 205\(\Omega\) (v) I = \(\frac{v}{z} = \frac{100}{205} = 0.49A\) (vi) P = I\(^2R\) = (0.49)\(^{2}\) x 100 = 23.795 W = 24W

(a)(i) Fusion is the coming together of two light nuclei to form a heavier nucleus with the release of large amount of energy \(^2_1H + ^3_1H \to ^4_2He\) + energy (ii) Fission is the breaking up of heavy nucleus into two nuclei of comparable masses when bombarded with neutrons releasing energy and neutrons in the process. \(^{235}_{92}U + ^1_0n \to ^{90}_{36}kr + ^{144}_{56}Ba + 2^1_0H + energy)\) (b) - Binding materials are cheap and easy to come by - it produces less dangerous products. - There is no e mass of hydrogen that can be obtained (c) Bonding energy = Mass of (Protons + neutron) - atomis mass = 27(1.00783u) + 32(1.00867u) - 58.93332 u = 27.21121u + 32.27744u - 58.9332 u = 59.48865 u - 58.9332 u = 0.55545 u = 0.55545 x 931 MeV = 517.12 x 10\(^6\) eV = 517.12 x 10\(^6\) x 1.6 x 10\(^{19}\) J = 8.27 x 10\(^{-11}\)J.