(a) Explain: (i) nuclear fission; (ii) nuclear fusion.
(b)(i) State three applications of atomic energy.
(ii) Define State. life.
(iii) Give the expression that relates the halflife, T, and the decay constant, X, of a radioactive material.
(c) A radioactive element X with atomic number 88 and mass number 226 emits in succession:
(i) an alpha particle, (ii) a beta particle and (iii) gamma radiation. Explain, using equations where necessary, the changes that take place in the atomic structure of the element at each stage.
(a) Define: (i) reactance; (ii) impedance.
(b)(i) Explain resonant frequency of an RLC circuit.
(ii) Explain the statement — the power supply voltage of a source is 230V
(c) A source of e.m.f 240V and frequency 50 Hz is connected to a series arrangement of a resistor, an inductor and a capacitor. When the current in the capacitor is 10A, the potential difference across the resistor is 140 V and that across the inductor is 50 V. Calculate the:
(i) potential difference across the capacitor (ii) capacitance of the capacitor; (iii) inductance of the indicator.
(d) Draw and label one vector diagram for the potential differences across the inductor, the capacitor and the resistor in (c) above.
(a) Define the following terms as applied to a convex mirror:
(i) principal focus; (ii) pole (iii) radius of curvature.
(b) State one advantage and one disadvantage of using a convex mirror as a driving mirror.
(c) Draw a clearly labelled diagram to illustrate how two converging lenses may be arranged to form a compound microscope.
(d) An object 2.5 mm long is viewed through a converging lens of focal length 10.0 cm held close to the eye. A magnified image of the object is formed 30.0 cm from the lens. Calculate the:
(i) distance of the object from the lens; (ii) size of the image; (iii) power of the lens.
(a) State Heisenberg’s uncertainty principle
(b) mention two phenomena that can only be explained in terms of the particulate nature of light
(a) (i) Define relative density.
(ii) List three characteristics of pressure in a liquid.
(b) The horizontal door of a submarine at a depth of 500m has an area of 0.4m\(^{2}\). Calculate the force exerted by the sea water on the door at this depth. [Relative density of sea water = 1.03 ] [Atmospheric pressure =- 1.01 x 10\(^{5}\) Nm\(^{-2}\)] [Density of pure water = 1000kgm\(^{-3}\)] [g = 10ms\(^{-2}\)]
(c) (i) List three effects of heat other than expansion.
(ii) Explain saturated vapour pressure.
(iii) A heating coil of resistance 20 \(\Omega\) connected to a 220 V source is used to boil a certain quantity of water in a container of heat capacity 100 J kg\(^{-1}\) for 2 minutes. If the initial temperature of the water is 40° C, calculate the mass of the water in the container. [specific heat capacity of water = 4.2 x 10\(^3\) Jkg\(^{-1}\) K\(^{-1}\)] [assume boiling point of water = 100°C]
(a) (i) What is meant by a machine?
(ii) List two examples of a simple machine.
(iii) Explain the statement — the velocity ratio of a machine is 5.
(b) (i) Define the efficiency of a machine.
(ii) Explain why a machine can never be 100% efficient.
(c) A screw jack, 25% efficient and having a screw of pitch 0.4 cm is used to raise a load through a certain height. If in the process, the handle turns through a circle of radius 40.0 cm, calculate the;
(i) velocity ratio of the machine; (ii) mechanical advantage of the machine; (iii) effort required to raise a load of 1000 N with the machine. [Take \(\pi\) =3.14]
Explain why a direct electric current is used instead of an alternating current in electroplating.
(a) Explain how neon signs can be produced.
(b) State two factors on which the colour of light from a fluorescent tube depend.
(a) What is meant by;
(i) anode;
(ii) cathode, as used in electrolysis?
(b) List the ions involved in an electrolytic process with dilute tetraoxosulphate (VI) acid as electrolyte
Explain the action of direct electric current in an electrolytic process with a dilute solution of sodium chloride as electrolyte
(a) Define horizontal range of a projectile.
(b) The horizontal range, R, of a projectile is given by the equation R = \(\frac{u^2 sin 2\theta}{g}\)
(i) what does \(\theta\) in the equation represent?
(ii) for what value of \(\theta\) would R be maximum?
A wire is gradually stretched until it snaps. Sketch a load-extension graph for the wire and on the graph indicate the
(a) elastic limit;
(b) yield point;
(c) maximum load;
(d) breaking point.
(a) What is diffusion?
(b) State two factors which affect the rate of diffusion.
Explain the rise of water in a glass capillary tube using the kinetic theory.
The colours seen on soap bubbles are due to
- A. Diffraction
- B. Refraction
- C. Dispersion
- D. Interference
If the total force acting on a particle is zero, the linear momentum will
- A. Increase
- B. Decrease
- C. Be Constant
- D. Increase then decrease
A bead travelling on a straight line wire is brought to rest at 0.2 by friction. If the mass of the bead is 0.01kg and the coefficient of friction between the bead and the wire is 0.1, determine the work done by the friction
[g = 10ms\(^2\)]
- A. 2 x 10\(^{-4}\)
- B. 2 x 10\(^{-3}\)
- C. 2 x 10\(^{-1}\)
- D. 2 x 10\(^2\)
Which of the following statements is true of the properties of a moving coil galvanometer?
- A. THe coil has a small area
- B. There are strong hair springs to gives a large control panlel
- C. There is a strong permanent magnet to give high magnetic flux
- D. it has a small number of turns of coil
A current of 0.5 A flowing 3h Deposits 2g of metal during electrolysis. The quantity of the same metal that would be deposited by the currents of 1.5A flowing in 1h is
- A. 2g
- B. 6g
- C. 10g
- D. 18g
At what frequency would a capacitor of 2.5μF
used in radio circuit have a resistance of 250Ω
- A. π/800 Hz
- B. 800/π Hz
- C. 200π Hz
- D. 2000π Hz