a) With the aid of diagrams, describe the three
characteristics of d.c. series motor.
(b) Briefly explain the difference between squirrel cage induction
motor and wound rotor induction
motor in terms of construction.
If the coefficient of kinetic friction between tires and dry
pavement is 0.90, what is the shortest distance in which you can
stop an automobile by locking the brakes when traveling at 22.9m/s
?
On wet pavement, the coefficient of kinetic friction may be only
0.25. How fast should you drive on wet pavement in order to be able
to stop in the same distance as in part A? (Note: Locking
the brakes is notthe safest way to stop.)
If...
If the coefficient of kinetic friction between tires and dry
pavement is 0.75, what is the shortest distance in which you can
stop an automobile by locking the brakes when traveling at 25.5 m/s
?
(a) With the aid of suitable diagrams
and examples explain the following terms:
(i)
surface tension
(ii) surface
free energy
(ii) surface
active agent (surfactant)
(iii) Krafft point
1)If the coefficient of kinetic friction between tires and dry
pavement is 0.800, what is the shortest distance in which an
automobile can be stopped by locking the brakes when traveling at
26.0m/s ?
2)On wet pavement the coefficient of kinetic friction may be
only 0.250. How fast should you drive on wet pavement in order to
be able to stop in the same distance as in part A? (Note:
Locking the brakes is not the safest way to stop.)