Related Mcqs:

1. While the recrystallisation temperature for pure metals is 0.3 Tm, the same for alloys is equal to ______________ × Tm (where, Tm Melting temperature) ?

   A. 0.25
   B. 0.45
   C. 0.70
   D. 0.95

2. Recrystallisation temperature of steel is ______________________ °C?

   A. 50
   B. 300
   C. 500
   D. 800

3. Boiling point of water gets lowered at high altitudes (e.g., hills), because ___________________?

   A. Temperature is low
   B. Atmospheric pressure is low
   C. Atmospheric pressure is high
   D. None of these

4. Corrosion rate cannot be lowered by reducing the ________________ of the corroding medium?

   A. Concentration
   B. Velocity
   C. Temperature
   D. None of these

5. The boiling & freezing points on a newly defined temperature scale in degree ‘D’ are 400°D & 100°D respectively. The temperature reading corresponding to 60°C on this new temperature scale will be equal to _____________ °D ?

   A. 140
   B. 180
   C. 240
   D. 280

6. Heating the Hypo-eutectoid steels to 30°C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite & ferrite structure is called_______________________?

   A. Tempering
   B. Hardening
   C. Annealing
   D. Normalising

7. The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K) ?

   A. T
   B. 1/T
   C. T2
   D. 1/T2

8. Which of the following parameters is not responsible for the heat loss from a hot steam carrying bare pipe surface located in a room without fans ?

   A. Emissivity of pipe surface
   B. Diameter & length of the pipe
   C. Temperature of hot pipe surface & that of air in the room
   D. None of these

9. Which of the following low melting alloy containing bismuth and lead is used for electric fuse ?

   A. Wood’s metal
   B. Babbitt metal
   C. Monel metal
   D. Duralumin

10. ____________________ of hard alloy and tool steel is done to make it easily machinable ?

    A. Case carburising
    B. Tempering
    C. Normalising
    D. Annealing