There is one paper of three hours duration of 100 marks. Section A of the paper contains short answer questions, all of which are to be answered. Section B of the paper contains six questions of which you must answer five questions.

**1. Strength of materials.** Simple problems. Hooke's law, stress and strain. Young's modulus. Tension and compression. Elastic limit. Ultimate strength. Factors of safety.

**2. Friction.** Conditions affecting friction. Lubrication. Conditions should include types of materials, their surface finish and wetness or dryness.

**3. Limiting friction.** Coefficients of friction.

**4. Work.** Work done by constant and by varying force; graphical representation of and calculations thereon. Energy, potential and kinetic. Conservation of energy and conversion into work, work done in rotation. Torque.

**5. Machines.** Simple single-string pulley systems. Simple and differential wheel and axle. Weston pulley block. Screw jack. Worm (single start thread and wheel). Gear and belt drives. Velocity ratio, mechanical advantage and efficiency.

**6. Power.** Simple treatment of steam and internal combustion engines. Indicators diagrams. Indicated mean effective pressure. Indicated and brake horsepower. Methods of measurement of power. Rope brake and Prony brake. Hydraulic power (as given by the product of constant pressure and rate of volume change). Mechanical efficiency.

Relationship between rev/min and working strokes per minute in double-acting steam engines and in two and four-stroke internal combustion engines. The oscillating cylinder steam engine is not required.

**7. Momentum.** Conservation of momentum, including rate of change of momentum and relationship with mass and acceleration. Knowledge of coefficient of restitution is not required.

**8. Magnetism.** Magnetic properties of iron and steel. The magnetic circuit; qualitative treatment only, with examples from transformers and machines. The compass needle. Magnetic effect of current in straight wire, single turn coil and solenoid, treated qualitatively. Electromagnets and their simple applications.

Relation of direction of current in conductor and lines of magnetic force applied. Examples of the application of electromagnets to include electric trembler bell and relay.

**9. The simple circuit.** Conductors and insulators. Electromotive force, potential difference, current, quantity and resistance; the volt, ampere, coulomb ampere-hour and ohm. Ohm's law. Measurement of resistance, including Wheatstone bridge, Resistivity. Resistors in series and in parallel.

**10. Heating effect of current.** Energy and power. Conversion of electrical to mechanical energy and vice versa. The joule, watt, and kilowatt-hour. Simple applications of heating effect. Effect of temperature on resistance. Temperature coefficient. Examples to include various domestic heating appliances and filament lamps.

**11. Chemical effect of current field.** Electrolytes. Electrolysis. Electrochemical equivalent. Production of current by chemical action. Simple voltaic cell. Primary and secondary cells.

Polarisation: prevention and removal. Cells in series and in parallel. Chemical equations are not required.

**12. Current-carrying conductor in magnetic field.** The D.C. motor including series and shunt windings. Galvanometers, voltmeters and ammeters. Shunts and multipliers. A qualitative treatment of multiple D.C. motors is included.

**13. Electromagnetic induction:** the laws of induction. Back e.m.f. of motor. Starting resistance for D.C. motor. Simple a.c. and D.C. generators. Relation of direction of lines of force, motion of conductor and current in coil. Eddy currents. Transformers.

The induction coil; the coil ignition system. A qualitative treatment of multipole D.C. generators is included.