1. Mild
steel is an alloy of iron and carbon with percentage of carbon ranging from
(a) up to 0.2%
(b) 0.15–0.3
(c) 0.3–0.5
(d) above 0.5.
2. IZOD
test measures
(a) hardness
(b) ductility
(c) impact-strength
(d) grain size.
3. Copper
is used for making electrical conductors because it is
(a) ductile
(b) resists
corrosion
(c) has low
resistance
(d) cheap.
4. Brass
is an alloy of
(a) copper and
zinc
(b) tin and zinc
(c) copper and tin
(d) copper and Al.
5. A
small amount of phosphorous is present in
(a) all bronzes
(b) phosphor-bronze
(c) tin bronze
(d) beryllium
bronze.
6. Which
test measures hardness?
(a) Brinell test
(b) Rockwell test
(c) Vicker’s test
(d) All of these
tests.
7. The
object of ‘normalising’ a steel specimen is
(a) to reduce
hardness
(b) to relieve
stresses
(c) to refine
structure
(d) to improve
ductility.
8. The
melting point of steel increases with
(a) reduced carbon
content
(b) increased
carbon content
(c) none of these.
9. The
strength of steel increases with increasing carbon %age in the range
(a) 0–0.8%
(b) 0.8–1.2%
(c) 1.2–2%
(d) all of these
ranges.
10. Aluminium
alloys find use in aircraft industry because of
(a) high strength
(b) low sp. gravity
(c) good corrosion
resistance
(d) good
weldability.
Answers
1. (b) 2. (c) 3. (c) 4. (a) 5. (a)
6. (d) 7. (c) 8. (a) 9. (a) 10. (b)