471. The design of shafts made of brittle materials is based on
Guest’s theory
Rankine’s theory
St Venant’s theory
VonMises theory
✅ The correct answer is option B.
Machine Design MCQs
472. A compound cylinder with inner radius 50 mm and outer radius 70 mm is made by shrinking one cylinder on to the other cylinder, The junction radius is 60 mm and the junction pressure is 1.1 N/mm2. The maximum hoop stress developed in the inner cylinder is
3.6 N/mm2 compression
3.6 N/mm2 tension
7.2 N/mm2 compression
7.2 N/mm2 tension
✅ The correct answer is option C.
473. The set screws are used to prevent relative motion between the two parts.
Correct
Incorrect
✅ The correct answer is option A.
474. For hardening alloy steels and high speed steels, they are heated to
500 to 600°C
700 to 900°C
1100 to 1300°C
1300 to 1500°C
✅ The correct answer is option C.
475. When a hole of diameter ‘d’ is punched in a metal of thickness ‘t’, then the force required to punch a hole is equal to (where τu = Ultimate shear strength of the material of the plate)
d.t.τu
πd.t.τu
x d2τu
x d2 x tτu
✅ The correct answer is option B.
476. The power transmitted by means of a belt depends upon
velocity of the belt
tension under which the belt is placed on the pulleys
arc of contact between the belt and the smaller pulley
all of the above
✅ The correct answer is option D.
477. The shock resistance of steel is increased by adding
nickel
chromium
nickel and chromium
cobalt and molybedenum
✅ The correct answer is option C.
478. A hollow shaft will transmit a __________ torque than a solid shaft of the same mass and same material.
smaller
greater
✅ The correct answer is option B.
479. In case of pressure vessels having closed ends, the fluid pressure induces
longitudinal stress
circumferential stress
shear stress
none of these
✅ The correct answer is option D.
480. In a journal bearing, the load on the bearing is __________ to the axis of the journal.
parallel
perpendicular
✅ The correct answer is option B.