1. a) Define the following as applied to circular motion:
i) Centripetal acceleration
ii) Period
b) i) Explain why a cyclist bends inwards while going round a curved path
ii) Show that if θ is the angle on inclination of the cyclist to the vertical and μ is the coefficient of limiting friction between the ground and the bicycle tyres, then for safe riding tan θ ≤ μ.
iii) A body of mass 1.5kg moves once round a circular path to cover 44.0cm in 5.0s. Calculate the centripetal force acting on the body.
c) Define simple harmonic motion
d) a body executes simple harmonic motion with amplitude A and angular velocity ω.
i) Write down the equation for the velocity of the body at a displacement x from the mean position.
ii) Sketch the velocity – displacement graph for the body in (d) (i) for ω<1
iii) If the body moves with amplitude 14.142cm, at what distance from the mean position will the kinetic energy be equal to potential energy?
2. a) State and illustrate Archimedes Principle.
b) i) State the law of floatation
ii) Describe an experiment to verify the law in (b) (i)
c) i) Write Bernouli’s equation and define each term in the equation
ii) Explain the origin of the lift force on the wing of a plane.
iii) Air flows over the upper surfaces of the wings of an aeroplane at a speed of 120ms-1, and past the lower surfaces of the wings at 110ms-1. Calculate the lift force on the aeroplane if it has a total wing area of 20m2. (Density of air = 1.29kgm-3)
3.a) Define moment of a force and give its SI unit.
b) Explain briefly how to locate the centre of gravity of an irregular sheet of cardboard
c) State the conditions necessary for equilibrium of a rigid body under the action of a system of forces.
d) A wheel of radius 0.5m rests on a level surface at point C and makes contact with edge E of a block of height 0.2m as shown below
A force F is applied horizontally through the axle of the wheel at X to just move the wheel over the block. If the weight of the wheel is 180N, find the;
i) force exerted at point E
ii) force F
e) State the laws of solid friction and explain each of them.
4. a) i) Distinguish between scalar quantity and vector quantity
ii) Give two examples of each type of quantity
b) A body of mass 0.2kg at rest is acted on by four forces of 2.8N, 6.0N, 4.5N and 1.2N as shown in figure 1
Calculate the;
i) resultant force on the body
ii) distance moved in 4s
c) State Newton’s laws of motion and use them to derive the law of conservation of momentum
d) A body of mass 800kg moving at 30ms-1 collides with another body of mass 1400kg moving in the same direction at 25ms-1. The two bodies stick together after collision. Calculate the;
i) common velocity just after collision
ii) Kinetic energy lost during the collision
5. a) i) What is meant by reversible process?
ii) Distinguish between a saturated vapour and unsaturated vapour
iii) Explain why evaporation causes cooling
b) Describe an experiment to determine the temperature dependence of saturated vapour pressure of water.
c) i) State Dalton’s law of partial pressures.
ii) A sealed container has liquid water, water vapour and air all at 270C. The total pressure inside the container is 69cmHg.
When the temperature is raised to 850C, the total pressure changes to 96cmHg.
If the saturation vapour pressure of water at 270C is 5cmHg and the water vapour remains saturated, calculate the saturated vapour pressure of water at 850C.
6. a) Define the following:
i) Thermal conductivity,
ii) Specific latent heat of vaporization
b) A boiler with a base made of steel 15cm thick, rests on a hot stove.
The area of the bottom of the boiler is 1.5 x 103cm2.
The water inside the boiler is at 1000C. If 750g of water is evaporated every 5 minutes, find the temperature of the surface of the boiler in contact with the stove.
(Thermal conductivity of steel = 50.2Wm-1 K-1, Specific latent heat of vaporization of water = 2.26 x 106 Jkg-1)
c) Hot water in a metal tank is kept constant at 650C by an immersion heater in the water.
The tank has a lagging all round it of thickness 20mm and thermal conductivity 0.04Wm-1 K-1 and its surface area is 0.5m2.
The heat lost per second by the lagging is 0.8W per degree excess above the surroundings.
Calculate the power of the immersion heater if the temperature of the surrounding is 150C.
d) i) Define a thermometric property
ii) Describe how a liquid-in-glass thermometer can be used to measure temperature in degrees Celsius.
iii) A thermometer is constructed with a liquid which expands according to relation;
Vt = V0 (1 + αt + βt2)
Where Vt is the volume at t0C and V0 is the volume at 00C on the scale of the gas thermometer and α and β are constants.
Given that a = 1000β, what will the liquid thermometer read when the gas thermometer reads 500C?
7. a) i) State any three properties of ultraviolet radiation.
ii) What is a black body?
b) A cylindrical metal rod with a well insulated curved surface has one end blackened and then exposed to thermal radiation from a body at a temperature 500K. If the equilibrium temperature of the blackened end is 400K and the length of rod is 10m, calculate the temperature of the other end. (Thermal conductivity of the metal = 500Wm-1 K-1)
c) i) Describe an electrical method of determining the specific heat capacity of a good conducting solid.
ii) Give an y two reasons why the value obtained using the method in (c) (i) may not be accurate.
d) Explain why cloudy nights are warmer than cloudless ones.
8.a) i) What is meant by thermionic emission?
ii) Describe how full-wave rectification of a.c can be achieved using four semiconductor diodes.
b) i) Draw a labeled diagram to show the main parts of a cathode ray oscilloscope (C.R.O)
ii) Describe how a C.R.O can be used as an a.c voltmeter
c) i) An electron of charge –e and mass m moves in a circular orbit round a central hydrogen nucleus of charge +e. Derive an expression for the total energy of the electron in an orbit of radius r.
ii) why is the energy always negative?
d)i) What is meant by excitation potential of an atom?
ii) Some of the energy levels in the mercury spectrum are shown below
A -------------0
B-------------- -5.5eV
C-------------- -10.4eV
Calculate the wave lengths of the radiation emitted when electron makes a transition from level A to level C
9. a) i) What are cathode rays?
ii) State two properities of cathode rays
iii) Explain two disadvantages of using the discharge tube in producing cathode rays.
b) With the aid of a diagram, describe Millikan’s experiment to determine the charge on an oil drop.
c) A beam of electrons is accelerated through a potential difference of 1.98kV and directed mid-way between two horizontal plates of length 4.8cm and separated by a distance of 2.0cm. The potential difference applied across the plates is 80.0V.
i) Calculate the speed of the electrons as they enter the region between the plates
ii) Explain the motion of the electrons as they emerge from the region between the plates.
10. a) What is meant by the following as applied to radioactivity?
i) Activity
ii) Half-life of a radioactive material
b) Using the radioactive decay law N=N0e-λt, show that the half-life T½ is given by;
T½ =
c) With the aid of a labeled diagram, describe the action of an ionization chamber
d) What is meant by unified atomic mass unit and electron volt
e) i) The nucleus 
decays by alpha emission as follows;
Calculate the energy released by 2g of
ii) Explain two used of radioactive isotopes.
END