Theory Of Machine MCQ Questions & Answers

21

The maximum efficiency of spiral gears is (where $$\theta $$ = Shaft angle and $$\varphi $$ = Friction angle)

A) $$\frac{{\sin \left( {\theta + \varphi } \right) + 1}}{{\cos \left( {\theta - \varphi } \right) + 1}}$$ B) $$\frac{{\cos \left( {\theta - \varphi } \right) + 1}}{{\sin \left( {\theta + \varphi } \right) + 1}}$$ C) $$\frac{{\cos \left( {\theta + \varphi } \right) + 1}}{{\cos \left( {\theta - \varphi } \right) + 1}}$$ D) $$\frac{{\cos \left( {\theta - \varphi } \right) + 1}}{{\cos \left( {\theta + \varphi } \right) + 1}}$$

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

22

The dedendum circle diameter is equal to (where, $$\varphi $$ = Pressure angle)

A) Pitch circle diameter × cos$$\varphi $$ B) Addendum circle diameter × cos$$\varphi $$ C) Clearance circle diameter × cos$$\varphi $$ D) Pitch circle diameter × sin$$\varphi $$

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

23

When the addenda on pinion and wheel is such that the path of approach and path of recess are half of their maximum possible values, then the length of the path of contact is given by (where r = Pitch circle radius of pinion, R = Pitch circle radius of wheel and $$\varphi $$ = Pressure angle)

A) $$\frac{{\left( {{{\text{r}}^2} + {{\text{R}}^2}} \right)\cos \varphi }}{2}$$ B) $$\frac{{\left( {{{\text{r}}^2} + {{\text{R}}^2}} \right)\sin \varphi }}{2}$$ C) $$\frac{{\left( {{\text{r}} + {\text{R}}} \right)\cos \varphi }}{2}$$ D) $$\frac{{\left( {{\text{r}} + {\text{R}}} \right)\sin \varphi }}{2}$$

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

24

Effort of a governor is the

A) Mean force exerted at the sleeve for a given percentage change of speed B) Work-done at the sleeve for maximum equilibrium speed C) Mean force exerted at the sleeve for maximum equilibrium speed D) None of the above

Discuss

Answer & Solution

Answer: Option A

No explanation is given for this question. Let's Discuss on Board

25

Power of a governor is the

A) Mean force exerted at the sleeve for a given percentage change of speed B) Work-done at the sleeve for maximum equilibrium speed C) Mean force exerted at the sleeve for maximum equilibrium speed D) None of the above

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

26

In a reciprocating steam engine, which of the following forms a kinematic link?

A) Cylinder and piston B) Piston rod and connecting rod C) Crankshaft and flywheel D) Flywheel and engine frame

Discuss

Answer & Solution

Answer: Option C

No explanation is given for this question. Let's Discuss on Board

27

The Coriolis component of acceleration acts

A) Along the sliding surface B) Perpendicular to the sliding surface C) At 45° to the sliding surface D) Parallel to the sliding surface

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

28

In a shaper mechanism, the Coriolis component of acceleration will

A) Not exist B) Exist C) Depend on position of crank D) None of the above

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

29

The instantaneous center of a rigid thin disc rolling on a plane rigid surface is located at

A) The center of the disc B) The point of contact C) An infinite distance on the plane surface D) The point on the circumference situated vertically opposite to the contact point

Discuss

Answer & Solution

Answer: Option B

No explanation is given for this question. Let's Discuss on Board

30

Which of the following statements regarding laws governing the friction between dry surfaces are correct?

A) The friction force is dependent on the materials of the contact surfaces. B) The friction force is directly proportional to the normal force. C) The friction force is independent of me area of contact. D) All of the above

Discuss

Answer & Solution

Answer: Option D

No explanation is given for this question. Let's Discuss on Board

Theory Of Machine MCQ Questions & Answers | Mechanical Engineering