Question 1
(a) State the reason why files without handles should not be used.
(b) Sketch an odd-leg calipers.
(c) Describe the production of pig iron with reference to the following:
(i)furnace used;
(ii)charge;
(iii)impurities.
(d) State two properties of each of the following:
(i) cast iron;
(ii) steel.
Observation
These did not pose much difficulty to the candidates as they responded well to parts (a), (c) and (d). Many of the candidates sketched other types of calipers (e.g inside calipers, outside calipers). The required responses are as follows:
1(a) Stating the reason why files without handles should not be used
- To prevent injuries
- To protect the user of the file so that the sharp point of the tang does not pierce the hand.
Sketching an odd-leg callipers
(c) (i) Pig iron is produced by using a blast furnace.
(ii) In the production of pig iron the charge consists of iron ore, coke and limestone.
(iii) The impurities are sulphur, silicon, phosphorous, manganese which combine with limestone to form the slag.
(d) Properties of cast iron – brittle, hard, rigid, self lubricating and castable.
Properties of steel – ductile, malleable, tough, strong, machinable.