Q1. What is annealing?

Answer – It is a process of heating a material above the re-crystallization temperature and cooling after a specific time interval. This increases the hardness and strength if the material.

Q2. What is ductile-brittle transition temperature?

Answer – It is the temperature below which the tendency of a material to fracture increases rather than forming. Below this temperature, the material loses its ductility. It is also called Nil Ductility Temperature.

Q3. Which theories of failure are used for (a) ductile materials and (B) brittle materials?

Answer – For ductile materials, theories of failure used are maximum shear stress theory, and maximum energy of distortion theory; while for brittle materials, the theory of maximum principal stress, and maximum strain are used.

Q4. What does thermal diffusivity of metals signify?

Answer – Thermal diffusivity is associated with the speed of propagation of heat into solids during changes in temperature with time.

Q5. What is enthalpy?

Answer – Enthalpy is the heat content of a chemical system.

Q6. What is a positive displacement pump?

Answer – A positive displacement pump causes a liquid or gas to move by trapping a fixed amount of fluid or gas and then forcing (displacing) that trapped volume into the discharge pipe. Positive displacement pumps can be further classified as either rotary-type (for example the rotary vane) or lobe pumps similar to oil pumps used in car engines. These pumps give a non-pulsating output or displacement, unlike the reciprocating pumps. Hence, they are called positive displacement pumps. Which parameter remains constant in a throttling process?

Q7. Which parameter remains constant in a throttling process?

Answer – Enthalpy

Q8. Which reactor produces more fissionable material than it consumes?

Answer – Breeder reactor.

Q9. Which reactor uses natural uranium as fuel?

Answer – Gas-cooled reactor.

Q10. Which reactor uses heavy water as a moderator?

Answer – CANDU.

Q11. Which reactor requires no moderator? 

Answer – Breeder reactor.

Q12. What is ferrite?

Answer – Magnetic iron rock

Q13. What is the difference between projectile motion and a rocket motion?

Answer – A projectile has no motor/rocket on it, so all of its momentum is given to it as it is launched. An example of a projectile would be a pen that you throw across a room.

A rocket or missile does have a motor/rocket on it so it can accelerate itself while moving and so resist other forces such as gravity.

Q14. Explain Otto cycle.

Answer – Otto cycle can be explained by a pressure-volume relationship diagram. It shows the functioning cycle of a four-stroke engine. The cycle starts with an intake stroke, closing the intake and moving to the compression stroke, starting of combustion, power stroke, heat exchange stroke where heat is rejected and the exhaust stroke. It was designed by Nicolas Otto, a German engineer.

Q15. What is a converter reactor? 

Answer – A reactor plant which is designed to produce more fuel than it consumes. The breeding is obtained by converting fertile material to fissile material.

Q16. Explain nuclear reactor in brief.

Answer – A plant which initiates, sustains, controls and maintains nuclear fission chain reaction and provides shielding against radioactive radiation is the nuclear reactor.

Q17. What is gear ratio?

Answer – It is the ratio of the number of revolutions of the pinion gear to one revolution of the idler gear.

Q18. Which heating value is indicated by a calorimeter and why?

Answer – Gross heating value because steam is condensed and heat of vapour formed is recovered.

Q19. What is annealing?

Answer – It is a process of heating a material above the re-crystallization temperature and cooling after a specific time interval. This increases the hardness and strength if the material.

Q20. What is fuel ratio? 

Answer – Fuel ratio is the ratio of its % age of fixed carbon to volatile matter.12. What is ductile-brittle transition temperature?