The advantage of oil filled cables is
more perfect impregnation
smaller overall size
all of the above
no ionisation oxidation and formation of voids
all of the above
The hot resistance of the bulbs filament is higher than its cold resistance because the temperature co-efficient of the filament is
positive
about 2 ohms per degree
negative
zero
positive
When one leg of parallel circuit is opened out the total current will
decrease
increase
reduce
become zero
decrease
In a lamp load when more than one lamp are switched on the total resistance of the load
none of the above
decreases
increases
remains same
decreases
Two lamps 100 W and 40 W are connected in series across 230 V (alternating). Which of the following statement is correct ?
40 W lamp will glow brighter
100 W lamp will glow brighter
Both lamps will glow equally bright
40 W lamp will fuse
40 W lamp will glow brighter
Resistance of 220 V 100 W lamp will be
4840 Q
48.4 Q
4.84 Q
484 ft
484 ft
In the case of direct current
magnitude and direction of current changes with time
magnitude of current changes with time
magnitude and direction of current remains constant
magnitude of current remains constant
magnitude and direction of current remains constant
When electric current passes through a bucket full of water lot of bubbling is observed. This suggests that the type of supply is
D.C.
none of the above
any of above two
A.C.
D.C.
Resistance of carbon filament lamp as the applied voltage increases.
decreases
remains same
increases
none of the above
decreases
Bulbs in street lighting are all connected in
end-to-end
parallel
series
series-parallel
parallel
पोस्ट अच्छी लगी हो तो प्लीज नीचे दिए गए लिंक पर क्लिक कर शेयर जरुर करें