cameroon gce ordinary level June 2022 physics 2

cameroon gce ordinary level June 2022 physics 2

cameroon gce ordinary level June 2022 physics 2

An uncalibrated mercury-in-glass thermometer is placed in steam from boiling water at standard atmospheric
pressure, and the length of the mercury thread is30 cm. It is then placed in melting ice and the length of the
thread drops to 5 cm. When it is placed in warm water, the length of the thread is 9.3 cm.
(i) Calculate the temperature of the warm water.
(ii) State a reason why water is not used as a thermometric liquid.
(b) On method of heat transfer through a material is called conduction.
(i) Define heat conduction.
(ii) State one advantage of heat conduction.
(iii) State one disadvantage of heat conduction.
(c) The specific heat capacity of copper is 400/ kg~1K ~1. A piece of copper of mass 10 kg is at a temperature of
80 °C. Calculate the amount of heat it must lose for its temperature to decrease to50 °C.

3. (a) State the principle of moments. (2 marks)
(b) A uniform beam is pivoted at its centre of gravity and different forces applied to it at different positions as
shown in Figure 2.
^ 3 m ** 2 mr 3 m T
30 N 40 N Pivot X N
Figure 2
Given that the beam is balanced, determine:
(i) the value of X.
(ii) the reaction force R acting at the pivot.
(2 marks)
(2 marks)
4. (a) State two factors that affect the resistance of a conductor.
(b) State two safety precautions taken in house wiring.
(c) State one reason why high tension lines are suspended high above the ground.
(d) State one advantage of transporting electricity as AC and not as DC.
5. A pulley system made up of 4 wheels is used to raise a load of 750 N unto a storey building under construction.
(2 marks)
(2 marks)
(a) What is the value of the velocity ratio of the pulley system? Explain.
(b) Given that the mechanical advantage of the machine is 3, calculate the effort applied.