Q.1 The minimum current a human can feel is approximately equal to __.
A. 5 mA
B. 1 mA
C. 10 mA
D. 15 mA
Ans.: B
Q.2 The perception of electric shock can be depends on the___.
A. magnitude of the voltage, frequency
B. duration of flow of current
C. current, path taken
D. All of the above
Ans.: D
Q. 3 The effect of an electric shock is/are___.
A. cause death
B. skin burns
C. Neurological effect
D. All of the above
Ans.: D
Q. 4 Death caused by an electric shock is known as___.
A. Neurological effect
Electrocution
C. Ash-flash hazards
D. none of the above
Ans.: B
Q. 5 ___ can occur if a human’s body comes in contact with any source of voltage enough high to force a sufficient current through the body.
A. electric hazards
B. electric shock
C. Earthing
D. None of the above
Ans.: B
Q. 6 The resistance of the earth should be maintained__ for domestic installation.
A. 1 Ohm
B. 3 Ohm
C. 5 Ohm
D. 10 Ohm
Ans.: C
Q. 7 ____ color of wire is used for earthing.
A. Red
B. Blue
C. Black
D. Green
Ans.: D
Q. 8 Disadvantages of earthing.
A. Very expensive due to the provision of a complete system of protective conductors, earth electrodes etc.
B. Possible safety hazard
C. Both A and B
D. none of the above
Ans.: C
Q. 9 A conductor which connects a part of an electrical installation, exposed conductive part to a earth electrode is known as___.
A. Earthing conductor
B. Earthing plate
C. Earth electrode
D. any of the above
Ans.: A
Q.10 _____ is the voltage occurring between the earthing system and reference earth at a given value of earth current flowing through earthing system.
A. Earth electrode
B. Earth voltage or earth potential
C. Earth resistivity
D. None of the above
Ans.: B
Q.11 Earth surface potential is the voltage between a point x on theearth’s surface and__.
A. Earth resistance
B. Earth potential
C. Reference earth
D. any af the above
Ans.: C
Q.12____ is the resistance, measured between two opposite faces.
A. Earth potential
B. Earth resistance
C. Earth resistivity or specific earth resistance
D. all of the above
Ans.: C
Q. 13 If moisture of earth is increases then earth resistance is ___.
A. Decrease
B. Increases
C. cannot changes
D. none of the above
Ans.: D
Q. 14 While designing Ground resistance which of the following is considered?
A. Ground resistance should be as high as possible
B. Ground resistance should be as low as possible
C. ground resistance should be zero
D. none of the above
Ans.: B
A. 1000 Ohms
B. 5000 ohms
C. 10 ohms
D. 100 ohms
Ans.: A