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c(ii) (a)(i) Define dew point. (ii) Explain why dew forms more quickly on the metal parts than on the rubber parts of a bicycle placed in the open overnight. (b)(i) Explain the statement. the specific heat capacity of copper is 400 J/kg/K. (ii) Two metals, P and Q are supplied with the same quantity of heat. If the ratio of the specific heat capacity of P to Q is 3: 1 and their masses are in the ratio I:2 respectively. calculate the ratio of the temperature rise of P to Q. (c)(i) Define coefficient of thermal conductivity of a material. The diagram above c(ii) illustrates a composite bar of iron and copper. The bar is insulated along its sides and it has a diameter of 10 mm. The length and thermal conductivity of the iron are 0.15 m and 40 W/m/K, respectively and those of copper are 0.05 m and 360 W/m/K, respectively. If the free ends of the iron and copper are kept at 100^\circC and 0^\circC respectively. calculate the (i) temperature at the interface between the bars; (ii) rate of heat flow along the bar.

The load-extension graph of an elastic material is illustrated above. Use the graph to determine the work done in stretching the material

Explain the wave-particle duality of light. (b) A particle of wavelength 4.2x 10\(^{-11}\)m travels (a) With a momentum of 1.6 x 10\(^{-23}\) kg m/s, Determine the value of the Planck's constant, h.

(a)(i) State the principal factor that determines the relative stability of a radioactive nucleus. (ii) Arrange the following radioactive nucleus in decreasing order of stability. Justify your answer: X,W and Y: \(^40{X}_20\) \(^920{Y}_36\) and \(^95{Z}_42\) (b)(i) Explain the term ionization potential. (ii) The diagram above illustrates energy levels in the hydrogen atom. E, is the energy of the E\(_0\) ground state. (i) When an electron makes a transition from level n = 3 to level n = 1, it emits a photon of wavelength 1.02x 10\(^{-7}\)m. Calculate E\(_0\). (ii) Calculate the ionization potential of the hydrogen atom. (c)(i) Explain the statement, the work function of sodium is 2.0 eV. (ii) Light of wavelength 160 mm is shone on the surface of a sodium metal of work function 2.0 eV. Determine whether photoelectrons will be emitted. [h = 6.6 x 10\(^{-34}\) Js, e = 3.0 x 10\(^{8}\)m/s, I eV = 1.6 x 10\(^{-19}\) J]

(a) You are provided with a set of masses, a metre rule, a thread, two retort stands and clamps, a stop watch, a knife edge and split corks. Carry out the following instructions using the diagram above as a guide. (i) Determine the centre of gravity, C, of the metre rule using the knife edge. (ii) Read and record the mass, M, of the metre rule written on the reverse side of it. (iii) Suspend the metre rule by means of two parallel threads of equal length, h =70 cm, with one at the 10 cm mark and the other at 90 cm mark of the metre rule. (iv) Attach a mass m = 30g firmly to the metre rule at C. Ensure that the graduated face of the metre rule is facing upwards and that d= 80 cm throughout the experiment. (v) Set the metre rule into small angular oscillations about the vertical axis through its centre of gravity by displacing its ends in opposite directions. (VI) Determine the time,i, for 20 oscillations and evaluate the period T, T\(^2\) and T\(^{-2}\). (vii) Repeat the procedure for four other values of m =40 g, 50 g, 60 g and 70 g n each case, determine I and evaluate T\(^2\) and T\(^{-2}\). (viii) Plot a graph of T on the vertical axis and m on the horizontal axis. (ix) Determine the slope, s, of the graph. (x) Evaluate Q= 0.68 / s. (xi) State two precautions taken to ensure accurate results. (b) (i) Give two examples of simple harmonic motion other than the motion of a simple pendulum. (ii) Explain the term centre of gravity of a body.

The force required to make an object of mass m, travelling with velocity v, turn in a circle of radius r is

A machine gun with a mass of 5kg fires a 50g bullet at a speed of 100 ms\(^{-1}\). The recoil speed of the machine gun is

What is the cost of running five 50W lamps and four 100W lamps for 10 hours if electrical energy costs 2 Kobo per KWh?

A solid weighs 4.8g in air, 2.8g in water and 3.2g in Kerosine. The ratio of density of the solid to that of the kerosine is

Consider the three forces acting at O and in equilibrium as shown in the figure. Which of the following equations is/are CORRECT? I. P\(_1\) cos \(\theta_1\) = p\(_1\) cos \(\theta_2\) II. P\(_3\) = P\(_1\) cos \(\theta_4\) + P\(_2 cos_2\) III. P\(_1 \sin \theta_1 = P_2 \sin \theta_2\)

The refractive index of a liquid is 1.5. If the velocity of light in vacuum is 3.0 x 10\(^8ms^{-1}\), the velocity of light in the liquid is

Heat is supplied uniformly at the rate of 100W to 1.0 x 10\(^{-2}\)kg of a liquid for 20 seconds. If the temperature of the liquid rises by 5\(^o\)C, then the specific heat capacity of the liquid is

The fiqure above represents a block-and-tackle pulley system on which an effort of W Newtons supports a load of 120.0N. If the efficiency of the machine is 40\(^o\), then the value of W is

In collision between two objects, kinetic energy is conserved only if

The quantity of motion of a body is its