If the co-efficient of adhesion on dry rails is 0.26, which of the following could be the value for wet rails ?

Related Mcqs:

1. The value of co-efficient of adhesion will be high when rails are_________________?

   A. greased
   B. wet
   C. sprayed with oil
   D. cleaned with sand

2. Due to which of the following co-efficient of adhesion improves ?

   A. Rust on the rails
   B. Dust on the rails
   C. Sand on the rails
   D. All of the above

3. Co-efficient of adhesion reduces due to the presence of which of the following ?

   A. Sand on rails
   B. Dew on rails
   C. Oil on the rails
   D. both B. and C.

4. Co-efficient of adhesion is________________-?

   A. high in case of D.C. traction than in the case of AC. traction
   B. low in case of D.C. traction than in the case of AC. traction
   C. equal in both AC. and D.C. traction
   D. any of the above

5. The normal value of adhesion friction is______________?

   A. 0.12
   B. 0.25
   C. 0.40
   D. 0.75

6. When a bogie negotiates a curve, reduction in adhesion occurs resulting in sliding. Thus sliding is acute when_______________?

   A. wheel base of axles is more
   B. degree of curvature is more
   C. both A. and B.
   D. none of the above

7. For three-phase induction motors which of the following is the least efficient method of speed control ?

   A. Cascade control
   B. Pole changing
   C. Rheostat control
   D. Combination of cascade and pole changing

8. If the value of collector current IC increases, then the value of VCE ______________?

   A. Remains the same
   B. Decreases
   C. Increases
   D. None of the above

9. In a certain five-step R/2R ladder network, the smallest resistor value is 1 kΩ. The largest value is___________?

   A. Indeterminable
   B. 2 kΩ
   C. 10 kΩ
   D. 20 kΩ

10. The value of stability factor for a base resistor bias is________________?

    A. RB (ß+1)
    B. (ß+1)RC
    C. (ß+1)
    D. 1-ß