3141. The process which improves the machinability of steels, but lowers the hardness and tensile strength is
normalising
full annealing
process annealing
spheroidising
✅ The correct answer is option D.
Mechanical Engineering
Prepare with the best Mechanical Engineering MCQs with answers and explanations for exams, interviews, and job tests. Our collection covers core topics such as engineering mechanics, thermodynamics, strength of materials, theory of machines, fluid mechanics, heat transfer, manufacturing processes, machine design, and power plant engineering. These Mechanical Engineering multiple-choice questions are designed for students, fresh graduates, and professionals preparing for NTS, PPSC, FPSC, PEC exams, GATE, university entry tests, and recruitment assessments. Strengthen your technical knowledge and problem-solving ability with our updated and comprehensive Mechanical Engineering MCQs.
3142. A body is said to be under forced vibrations, when
there is a reduction in amplitude after every cycle of vibration
no external force acts on a body, after giving it an initial displacement
a body vibrates under the influence of external force
none of the above
✅ The correct answer is option A.
3143. The ratio of surface convection resistance to the internal conduction resistance is known as
Grashoff number
Biot number
Stanton number
Prandtl number
✅ The correct answer is option B.
3144. The distance between the centre of a rivet hole to the nearest edge of plate, is called
margin
pitch
back pitch
diagonal pitch
✅ The correct answer is option A.
3145. A machine which violates the first law of thermodynamics is known as perpetual motion machine of the second kind.
Correct
Incorrect
✅ The correct answer is option B.
3147. In a four stroke cycle engine, the sequence of operations is
suction, compression, expansion and exhaust
suction, expansion, compression and exhaust
expansion, compression, suction and exhaust
compression, expansion
✅ The correct answer is option A.
3148. The material in which the atoms are arranged chaotically, is called
amorphous material
mesomorphous material
crystalline material
none of these
✅ The correct answer is option A.
3149. In order to double the period of a simple pendulum, the length of the string should be
halved
doubled
quadrupled
none of these
✅ The correct answer is option C.
3150. In a high pressure compressor, the delivery pressure is
1 to 5 bar
5 to 8 bar
8 to 10 bar
10 to 15 bar
✅ The correct answer is option C.