Review Questions

REVIEW QUESTIONS

1. Explain the uses of brakes in automobiles.

2. Differentiate between brakes and dynamometer.

3. Differentiate between brake and clutch.

4. What are block brakes? Derive an expression relating the applied force and braking torque in a block brake.

5. With neat sketch explain the working principle of a simple shoe brake, Also derive an expression for braking torque for different directions of rotation of drum.

6. Explain the working of a double shoe brake with the help of a line diagram. How do you calculate the brake torque for this?

7. What is the difference in simple and differential band brake? Which would be preferred? 

8. Derive an expression for braking torque on the drum of simple band brake.

9. In a simple band brake, one end of the band is attached to the fulcrum of a lever. The other end is attached at a distance of 'b' from the fulcrum. The effort is applied at the end of the lever. Derive an expression for braking torque, in terms of effort.

10. What is self-energizing brake. Derive self-locking conditions for a differential band brake when drum rotates in clockwise direction.

11. Explain the self-locking of brakes.

12. Derive expression for total braking torque about fulcrum in differential band brake, when brake drum rotating in counter clockwise direction.

13. Explain the arrangement done in band and block brake system. In what way it is superior to band brake?

14. Derive an expression for ratio of maximum and minimum tensions in a band and block brake.

15. Describe with the help of a neat sketch the principles of operation of an internal expanding shoe. Also deduce the expression for the braking torque.

16. In which case the retardation is more and why (a) when the front wheels are braked, (b) when the rear wheels are braked?