CBSE
A light emitting diode (LED) has a voltage drop of 2 volt across it and passes a current of 10 mA when it operates with a 6 volt battery through a limiting resistor R. The value of R is
40 kΩ
4 kΩ
200 kΩ
400 kΩ
In communication with help of antenna if height is dobled then the range covered which was initially r would become
3r
4r
5r
In the half wave rectifier circuit operating from 50 Hz mains frequency, the fundamental frequency in the ripple would be
25 Hz
50 Hz
70.7 Hz
100 Hz
An amplifier has a voltage gain Av = 1000. The voltage gain in dB is
30 dB
60 dB
3 dB
20 dB
The circuit given below represents which of logic operations?
AND
NOT
OR
NOR
A transistor is a/an
chip
insulator
semiconductor
metal
When a p-n diode is reverse biased,then
no current flows
the depletion region is increased
the depletion region is reduced
the height of the potential barrier is reduced
The minimum potential difference between the base and emitter required to switched a silicon transistor ON is approximately
1 V
3 V
5 V
4.2 V
The number 0 (zero) is required for
transistor
abacus
computer
calculator
Zener diode acts as a/an
oscillator
regulator
rectifier
filter