Top 1000+ Solved Material Science MCQ Questions Answer
Q. in use of special alloys, for cast irons, addition of increases the corrosion resistance
a. cr
b. ni
c. si
d. all of the above
Q. in corrosion prevention, the metal to be protected from corrosion is forced to behace like cathode in protection method
a. anodic
b. cathodic
c. both a and b
d. none of the above
Q. is a type of cathodic protection to prevent corrosion
a. sacrificial anodic or galvanic protection
b. impressed current cathodic protection
c. both a and b
d. none of th e above
Q. in cathodic protection, the commonly used sacrificial anode is
a. al
b. mg
c. zn
d. all of the above
Q. is the advantage of sacrificial anodic protection
a. no external power is required
b. it is easy to install
c. installation can be inexpensive if installed at the time of constuction
d. all of the above
Q. is the limitation of sacrificial anodic protection
a. poorly coated structures may require many anodes
b. it can be ineffective in high resistivity environment
c. installation can be expensive if installed after construction
d. all of the above
Q. is the application od sacrificial anodic protection
a. buried pipelines
b. underground cables
c. marine structures
d. all of the above
Q. in , an impressed external current is applied in the opposite direction to the metal to nullify the corrosion current
a. impressed current mehtod ofcathodic
b. sacrificial anodic protection
c. galvanic anodic protection
d. anodic protection
Q. is the advantage of impressed current method of cathodic protection
a. it can be designed for a wide range of voltage and current
b. it can be applied in high resistivity environment
c. effective in protecting uncaoted and poorly coated structures
d. all of the above
Q. is the limitation of impressed current method of cathodic protection
a. it can cause cathodic interference problems
b. require peroidic maintenance
c. require external power, resulting in monthly power costs
d. all of the above
Q. is the application of impressed current method of cathodic protection
a. open water box coolers
b. condensers
c. laid up ships
d. all of the above
Q. is the phenomenon in which a metal or an alloy exibits higher corrosion resistabce than expected from its position in the electrochemical series by forming protective, thin, nonporous oxide film on the surface
a. activity
b. passivity
c. both a and b
d. none of the above
Q. passivity phenomenon of anodic protection is quite common with metal like
a. al
b. ni
c. tin
d. all of the above
Q. in protection method, the part of metal to be protected from corrosion is made anodic by passing an impressed direct current in the same direction as that of corrosion current
a. sacrificial anodic or galvanic protection
b. galvanic protection
c. anodic protection
d. impressed current of cathodic protection
Q. is ha davantage of anodic protection to prevent corrosion
a. anodic protection has greaterthrowing
b. method can be applied to severlycorrosiong
c. it requires low current density,hence its
d. all of the above