Safety

#1. In arc welding voltage required to maintain the arc is in the range of....?

50-75 volts

100-200 volts

20-30 volts

160-230volts

incorrect current range;60 to 600A

#2. Danger 440V' plates are...?

advisory notice

danger notice

caution notice

informal notice

#3. Which motor should not be used for centrifugal pumps?

series

shunt

cumulative compound

differential compound

#4. A domestic mixer uses .... motor?

induction

reluctance

universal

synchronous

#5. Filament lamp operate at power factor of .....?

unity

0.5 lagging

0.6 leading

0.8 leading

#6. Which motor used in electric traction?

universal

series

shunt

compounf

#7. Ground resistance should be designed such that it is...?

200 ohms

as low as possible

as high as possible

100 ohms

#8. Ceramic rings are used as...?

bonding agent

impedence regulator

insulator

strong coupler

#9. The conductor used in wiring should be of...?

steel

copper

iron

tin

#10. Current transformer uses...?

step down transformer

step up transformer

potential transformer

centre tap transformer

#11. Grid synchronization failure can cause....?

heavy harmonics

lower power factor

higher power noise

burnt generator

#12. Which circuit breaker is used for 1.5 T air conditioner?

20A

5A

1A

2A

#13. When connected to bypass a prrotective circuit is known as...?

ELCB

MCB

Jumber

Contractor

#14. Which of the following is used as the heating unit of an electric kettle?

inductive filament

concealed wire in metal tube

flat wire sealed

open filament

#15. What should be the height of a single pole switch?

1.3 m

3 m

2.75 m

1.5 m

#16. The type of earthing suitable for sandy areas is....?

strip earthing

pipe

rod

plate

#17. How can the speed of a table fan be controlled?

by controlling frequency

by controlling input voltage

by controlling wave shape

by controlling current

#18. Earthing wires are usually made from...?

aluminium

galvanised steel

iron

copper

#19. According to N.E rule the colour code for the neutral wire is....?

red

green

black

blue

#20. As per indian electricity standard, What is the allowable voltage variation in low or medium voltage supply?

2%

4%

6%

10%