# Mechanical Interview Questions 3

Mechanical Interview Questions 3 contains questions about Otto cycle, nomenclature of a 6203-ZZ bearing, Gear ratio, Annealing, Torque, Ductile-Brittle Transition Temperature,  Auto Dosing,  Codes, Standards and Specifications.

21. How many Joules is 1 BTU?

22. What is PS?

23. Explain Otto cycle.

24. Explain the nomenclature of a 6203-ZZ bearing.

25. What is Gear ratio?

26. What is Annealing?

27. Define Torque.

28. What is Ductile-Brittle Transition Temperature?

29. What is Auto Dosing?

30. Difference between Codes, Standards and Specifications?

21. How many Joules is 1 BTU?

1 BTU is equal to 1055.056 joules.

22. What is PS?

PS is Pferdestarke, the German unit for Horsepower.

23.Explain Otto cycle.

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.

24. Explain the nomenclature of a 6203-ZZ bearing.

6 is the type code, which shows it is a single-row ball bearing,

2 is the series, means light,

03 is the bore, which is 17 mm and

ZZ is the suffix meaning double shielded bearing.

25. What is Gear ratio?

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

26. What is Annealing?

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.

27. Define Torque.

Torque is defined as a force applied to an object that results in rotational motion.

28. What is Ductile-Brittle Transition Temperature?

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.

29. What is Auto Dosing?

Auto dosing is an automated system of feeding the equipment with liquid products.

It is the ideal way to ensure the correct calibrated dose at the right time every time in auto.

30. Difference between Codes, Standards and Specifications?

1. Code is procedure of acceptance and rejection criteria.
2. Standard is accepted values and compare other with it.
3. Specification is describing properties of any type of materials.