126. Optical activity is a/an __________ property.
A. Additive
B. Constitutive
C. Both A & B
D. Neither A nor B
✅ The correct answer is option C.
129. Closeness of packing is maximum in case of __________ crystal lattice.
A. Face centred
B. Simple cubic
C. Body centred
D. None of these
✅ The correct answer is option A.
91. Which of the following is resistant to the action of both heat & chemicals?
A. Boro silicate glass
B. Silica glass
C. Soda lime glass
D. None of these
✅ The correct answer is option A.
94. Hot extrusion process is not used for making
A. Cast iron pipe for domestic water supply
B. Aluminium curtain rods
C. Stainless steel tubes used in furnitures
D. Any of these
✅ The correct answer is option A.
97. The materials which fracture even at small strains are termed as brittle, while those materials which exhibit an appreciable deformation before failure are termed as
A. Rigid
B. Tough
C. Ductile
D. Plastic
✅ The correct answer is option C.
100. Particle nature of cathode rays is proved due to the fact that they
A. Travel in a straight line
B. Get deflected by magnetic electric field
C. Produce fluorescence
D. Heat the exposed material
✅ The correct answer is option B.
103. Yield strength of a polycrystalline metal with an average grain size, d, is proportional to
A. d1/2
B. d-1/2
C. d
D. d-1
✅ The correct answer is option B.
106. Which of the following is not the commercial name of polymethyl-methacrylate (PMMA)?
A. Styrofoam
B. Lucite
C. Perspex
D. Plexiglass
✅ The correct answer is option A.
109. Filler material used in welding should have __________ as compared to the parent metal to be welded.
A. Lower melting temperature
B. Same melting temperature
C. Same composition
D. Both B & C
✅ The correct answer is option D.
73. Which of the following alloying elements when added in steel does not improve its lachinability?
A. Sulphur
B. Phosphorous
C. Copper
D. Lead
✅ The correct answer is option C.