Q1. Eutectoid composition of carbon steel at room temperature is
Q2. Which of the following is an unconventional source of energy?
(A) Thermal power
(B) Hydroelectric power
(C) Nuclear-fusion power
(D) Solar power
Q3. The refrigerant freon-12 is chemically
Q4. Temperature of hot gases flowing in a pipe is measured by a thermocouple inserted in the thermal well. The thermal well made of __________ will facilitate the most accurate measurement of the temperature.
Q5. Water-tube boiler is the one, in which
(A) Water passes through tubes and flue gases around it
(B) Tube carrying hot flue gases are immersed in a pool of water
(C) Tubes are placed in vertical position
(D) None of these
Q6. Silicon in steel
(A) Makes it usable in almost all magnetic circuits where alternating current is used
(B) Increases its electrical resistivity and decreases the hysteresis loss
(C) Is present upto 5% & 4% respectively when used in transformers & motor armatures
(D) All ‘a’, ‘b’ & ‘c’
Q7. Ferromagnetic materials owe their properties to __________ inner sub-shells.
(A) Completely filled
(B) Partially filled
(C) Equally filled
Q8. Superheating of steam is done at constant
Q9. The yield point phenomenon observed in annealed low carbon steel is due to the presence of the following element.
Q10. Corrosion is
(A) A physical phenomenon
(B) A chemical phenomenon
(C) Same as erosion
(D) An uncontrollable phenomenon