Iω2
Iω2
IωωP
IωωP
✅ The correct answer is option D.
Theory of machines MCQs
382. A watt’s governor can work satisfactorily at speeds from
60 to 80 r.p.m.
80 to 100 r.p.m.
100 to 200 r.p.m.
200 to 300 r.p.m.
✅ The correct answer is option A.
383. The acceleration of the particle moving with simple harmonic motion is __________ at the mean position.
zero
minimum
maximum
✅ The correct answer is option A.
384. The primary unbalanced force due to inertia of reciprocating parts in a reciprocating engine is given by (where m = Mass of reciprocating parts, ω = Angular speed of crank, r = Radius of crank, θ = Angle of inclination of crank with the line of stroke, and n = Ratio of the lengm of connecting rod to radius of crank)
m.ω2.r sin θ
m.ω2.r cos θ
m.ω2.r
m.ω2.r
✅ The correct answer is option B.
385. The ratio of maximum fluctuation of speed to the mean speed is called
fluctuation of speed
maximum fluctuation of speed
coefficient of fluctuation of speed
none of these
✅ The correct answer is option C.
386. When the crank is at the inner dead centre, in a reciprocating steam engine, then the acceleration of the piston will be
✅ The correct answer is option A.
387. The lower pairs are __________ pairs.
self-closed
force-closed
✅ The correct answer is option A.
388. In a kinematic chain, a quaternary joint is equivalent to
one binary joint
two binary joints
three binary joints
four binary joints
✅ The correct answer is option C.
389. The relation between the controlling force (Fc) and radius of rotation (r) for a stable spring controlled governor is
Fc = ar + b
Fc = ar – b
Fc = ar
Fc = a/r + b
✅ The correct answer is option B.
390. The efficiency of a screw jack is dependent upon the load raised or lowered.
TRUE
FALSE
✅ The correct answer is option B.