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

The temperature coefficient of resistance is given by \alpha = \(\frac{\text{Increase in resistance per ºC rise in temp}}{\text{resistance at 0ºC}}\) And for metals where resistance increases with temperature rise, the temperature coefficient of resistance is positive; on the other hand, in semiconductors, where resistance decreases with temperature rise, the temperature coefficient of resistance is negative.

When water freezes to ice, it undergoes anomalous expansion. Water's volume actually increases by approximately 9% as it turns into ice.

Teapots are often silver-coated to prevent heat loss by reflecting infrared radiation. Silver is a good reflector of thermal radiation, which helps to minimize heat loss from the teapot, keeping the contents warm for a longer period.

Safety gap = expansion of the rod = \(\alpha \times L_0 \times \Delta t\) where \(\alpha\) = linear expansivity of the material \(L_0\) = Initial length of the material \(\Delta t\) = Change in temperature \(\therefore\) The safety gap = \(2 \times 10^{-5} \times 20 \times (75 - 25)\) = \(2 \times 10^{-5} \times 10^3\) = \(2 \times 10^{-2} m\) = 0.02 m

The viscosity of a liquid depends on: * Nature of the liquid: Different liquids have varying viscosities. * Temperature of the liquid: Higher temperatures generally reduce viscosity. The area of the liquid surface does not affect viscosity, it is an intrinsic property of the liquid.

Specific Heat Capacity of mercury and water are 0.14 Jg\(^{-1}\)C\(^{-1}\) and 4.186Jg\(^{-1}\)C\(^{-1}\) respectively.

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

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

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

(a) Diffusion is the process by which substances mix with one another due to the random motion of their molecules. (b) Graham's law of diffusion states that the rate of diffusion of gases is inversely proportional to the square - root of their densities provided temperature remains constant.

1. \(v_o\) = 3.0v 2. \(V_R\) = 0.20 volts 3. l = 0.20, 1\(^{-1}\) = \(\frac{1}{1} = \frac{1}{0.2}\) = 5 V = 0.2, V\(^{-1}\) = \(\frac{1}{V} =\frac{1}{0.2}\) = 5 Table of values/observations S/N IA I\(^{-1}\)(A\(^{-1}\)) V(volts) V\(^{-1}\)(volts\(^{-1}\)) 1 0.20 5.00 0.19 5.26 2 0.25 4.00 0.23 4.35 3 0.30 3.33 0.28 3.57 4 0.35 2.86 0.33 3.03 5 0.40 2.50 0..38 2.63 Slope (s) = \(\frac{\bigtriangleup {V}^{-1}}{\bigtriangleup {I}^{-1}}\) S = \(\frac{5.1-1.0}{4.55-12} = \frac{4.1}{3.35}\) = 1.224 S\(^{-1}\) = \(\frac{1}{s} = \frac{1}{1.224}\) = 0.817 N.B: R = S\(^{-1}\) = 1.0 Precautions taken to ensure accurate results are as follows Tight connections ensured/clean terminals Repeated readings have been shown on the table Parallax error in reading voltmeter/ammeter avoided Key open when reading is not being taken (b)i. An ohmic conductor is s Conductor in which the current passing through it is proportional to the p.d across the conductor, provided temperature and other physical conditions are constant. ii. The resistivity of the material of a wire is the resistance of a unit length of the wire of unit Crofs sectional area. It is denoted by p. and measured in ohm-metre (L-m).

Two thermal objects are said to be in a thermal equilibrium when the temperature of both objects are equal. Generally, heat flows from an object at a higher temperature to the one at a lower temperature until both temperature are the same, during which the two bodies are said to be in thermal equilibrium

The increase in length of the steel rail is given by = α 10 = 11 x 10-6 x 20 x (40 -20) = 11 x 10-6 x 20 x 20 = 4.4 x 10-3 ∴ Final length will be original length plus increase in length = 20 + 4.4 x 10-3 = 20 + 0.0044 = 20.0044m

mc\DeltaT = Pt → 5 x c x 30 = 2000 x 10 x 60 c = \(\frac{1200000}{150}\) c = 8000 = 8.0 x \(10^3J/kgºC^{-1}\) But, Heat capacity C = mass x specific heat capacity C = 5 x 8000 = 40000 = 4 x (10^4JºC^{-1}\) (OR) C = \(\frac{2000* 10* 60*}{30}\) = 40,000JºC\(^{-1}\)