Review Questions

REVIEW QUESTIONS

1. Explain the following terms: (a) Resistant body; (b) Kinematic link; (c) Kinematic pair; (d) Kinematic chain; and (e) Mechanism.

2. Differentiate between the following terms:

(a) Resistant body and rigid body, (b) Machine and structure,

(b) Machine and mechanism, and (c) Lower pair and higher pair.

3. What do you mean by constrained motion? What are the different types of pairs having constrained motion? Explain each type with examples and neat sketches.

[Hint: Refer Section 1.4]

4. Explain different kinds of kinematic pairs with examples.

5. Derive the equation to determine the degree of freedom of a planar mechanism. Prove that a cam-roller follower mechanism is an exception for the above equation.

6. Explain Kutzbach criterion for the mobility of a mechanism with suitable example.

7. Sketch and explain the inversion of a four-bar mechanism, all the four pairs are turning pairs.

[A.U., Nov/Dec 2006; Nov/Dec 2011]

[Hint: Refer Section 1.13]

8. Sketch and describe the working of two different types of quick-return mechanisms. Derive an expression for the ratio of time taken in forward and return stroke for one of these mechanisms.

[A.U., Nov/Dec 2006]

[Hint: Refer Sections 1.15.2.1 and 1.15.3.2]

9. Sketch a slider-crank chain and its various inversions stating actual machines which they are used in practice.

[A.U., May/June 2007; Nov/Dec 2010; Apr/May 2011; Nov/Dec 2012]

[Hint: Refer Section 1.15]

10. Explain with neat sketches and their kinematic differences, two different inversions of a single slider-crank chain that can be used for the same application in machine tools.

11. Illustrate a crank and slotted lever mechanism as an inversion of single slider-crank chain. Deduce an expression for length of stroke in terms of link lengths.

12. Sketch and explain Whitworth quick-return mechanism.

13. Sketch and explain three inversions of a double slider-crank chain.

[A.U., Nov/Dec 2011; Nov/Dec 2013]

 [Hint:Refer Section 1.17]

14. Prove, with neat sketches, that an elliptical trammel can be used to trace many ellipses and one circle.