Theory of Machines Objective Question and Answer - Set 27 - ObjectiveBooks

# Practice Test: Question Set - 27

1. In a reciprocating steam engine, when the crank has turned from inner dead centre through an angle θ, the angular velocity of the connecting rod is given by
(A) ω sinθ/(n² - sin²θ)1/2
(B) ω cosθ/(n² - cos²θ)1/2
(C) ω sinθ/(n² - cos²θ)1/2
(D) ω cosθ/(n² - sin²θ)1/2

2. The efficiency of a screw jack is maximum, when (where α = Helix angle, and φ = Angle of friction)
(A) α = 45° + φ/2
(B) α = 45° - φ/2
(C) α = 90° + φ
(D) α = 90° - φ

3. When two pulleys of different diameters are connected by means of an open belt, the angle of contact at the ________ pulley must be taken into consideration.
(A) Smaller
(B) Larger
(C) Either A or B
(D) None of these

4. With single Hooke's joint it is possible to connect two shafts, the axes of which have an angular misalignment up to
(A) 10°
(B) 20°
(C) 30°
(D) 40°

5. The approximate straight line mechanism is a

6. When a point at the end of a link moves with constant angular velocity, its acceleration will have
(B) Tangential component only
(C) Coriolis component only
(D) Radial and tangential components both

7. The minimum force required to slide a body of weight W on a rough horizontal plane is
(A) W sinθ
(B) W cosθ
(C) W tanθ
(D) W cosecθ

8. The length of a simple pendulum which gives the same frequency as the compound pendulum, is
(A) kG + l₁
(B) kG² + l₁
(C) (kG² + l₁²)/ l₁
(D) (kG + l₁²)/ l₁

9. The unbalanced force due to revolving masses
(A) Varies in magnitude but constant in direction
(B) Varies in direction but constant in magnitude
(C) Varies in magnitude and direction both
(D) Constant in magnitude and direction both

10. The maximum fluctuation of energy is the
(A) Difference between the maximum and minimum energies
(B) Sum of the maximum and minimum energies
(C) Variations of energy above and below the mean resisting torque line
(D) Ratio of the mean resisting torque to the work-done per cycle

11. An imaginary circle which by pure rolling action, gives the same motion as the actual gear, is called
(B) Dedendum circle
(C) Pitch circle
(D) Clearance circle

12. Which of the following is an example of sliding pair?
(A) Piston and cylinder of a reciprocating steam engine
(B) Shaft with collars at both ends fitted into a circular hole
(C) Lead screw of a lathe with nut
(D) Ball and a socket joint

13. Pitch point of a cam is
(A) A point on the pitch curve having minimum pressure angle
(B) A point on the pitch curve having maximum pressure angle
(C) Any point on the pitch curve
(D) Any point on the pitch circle

14. The acceleration of a flat-faced follower when it has contact with the flank of a circular arc cam, is given by
(A) ω² R cosθ
(B) ω² (R - r₁) cosθ
(C) ω² (R - r₁) sinθ
(D) ω² r₁ sinθ

15. Ackermann steering gear consists of
(A) Sliding pairs
(B) Turning pairs
(C) Rolling pairs
(D) Higher pairs

Show and hide multiple DIV using JavaScript View All Answers

Blogger Comment