Which of the following will need the highest level of illumination ?
Railway platforms.
Hospital wards
Bed rooms
Proof reading
Proof reading
Which of the following will need lowest level of illumination ?
Displays
Fine engraving
Railway platform
Auditoriums.
Railway platform
Which of the following lamp gives nearly monochromatic light ?
Sodium vapor lamp
Mercury vapor lamp.
Tube light
GLS lamp
Sodium vapor lamp
The illumination level in houses is in the range
100-140 lumen/m2.
30 - 50 lumen/m2
10-20 lumen/m2
40-75 lumen/m2
100-140 lumen/m2.
Luminous efficiency of a fluorescent tube is
30 - 40 lumens/watt
60 - 65 lumens/watt.
5- 10 lumens/watt
15-20 lumens/watt
60 - 65 lumens/watt.
One lumen per square meter is the same as
One lux
One candela
One foot candle
One lumen meter.
One lux
For a particular material the Hall coefficient was found to be zero. The material is
none of the above
intrinsic semiconductor
insulator
metal
metal
is an element used in semiconductors whose atoms have three valence electrons.
A donor
Germanium
An acceptor
Silicon
An acceptor
The minority carrier concentration is largely a function of
temperature
the amount of doping
reverse biasing voltage
forward biasing voltage
temperature
For germanium the forbidden energy gap is
0.7eV
0.25 eV
0.15 eV
0.5eV
0.7eV
पोस्ट अच्छी लगी हो तो प्लीज नीचे दिए गए लिंक पर क्लिक कर शेयर जरुर करें
0 Comments