661. The most economical section of a trapezoidal channel is one which has hydraulic mean depth equal to
1/2 depth
1/2 breadth
1/2 sloping side
1/4 (depth + breadth)
✅ The correct answer is option A.
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.
662. The moment of a force
is the turning effect produced by a force, on the body, on which it acts
is equal to the product of force acting on the body and the perpendicular distance of a point and the line of action of the force
is equal to twice the area of the traingle, whose base is the line representing the force and whose vertex is the point, about which the moment is taken
all of the above
✅ The correct answer is option D.
663. Alpha-methyl-naphthalene (C11 H10) has a cetane number of
0
50
100
120
✅ The correct answer is option A.
664. The metal suitable for bearings subjected to heavy loads is
silicon bronze
white metal
monel metal
phosphor bronze
✅ The correct answer is option B.
665. A process, in which the gas is heated or expanded in such a way that product of its pressure and volume remains constant, is called isothermal process.
Yes
No
✅ The correct answer is option B.
666. The operation of cutting a sheet of metal in a straight line along the length, is known as
plunging
notching
slitting
forming
✅ The correct answer is option C.
667. Kirchhoff’s law states that
the total radiation from a black body per second per unit area is directly proportional to the fourth power of the absolute temperature
the wave length corresponding to the maximum energy is proportional to the absolute temperature
the ratio of the emissive power and absorptive power of all bodies is the same and is equal to the emissive power of a perfectly black body
none of the above
✅ The correct answer is option C.
668. When an open coiled helical compression spring is subjected to an axial compressive load, the maximum shear stress induced in the wire is (where D = Mean diameter of the spring coil, d = Diameter of the spring wire, K = Wahl’s stress factor, and W = Axial compressive load on the spring)
✅ The correct answer is option D.
669. In a receiver type compound engine, the high pressure and low pressure cylinders
have common piston rod
are set at 90°
have separate piston rods
are set in V – arrange
✅ The correct answer is option C.
670. Oil separator in a refrigeration cycle is installed
before compressor
between compressor and condenser
between condenser and evaporator
between condenser and
✅ The correct answer is option B.