Electronic Science - Online Test
Q1. For a one dimensional electric field the correct relation of and potential V is
Answer : Option B
Explaination / Solution:
Electric field is defined as the negative gradient of the potential. The potential decreases in the direction of the electric field.
Q2. Which of the following is true?
Answer : Option A
Explaination / Solution:
Trivalent impurities are used for making p - type semiconductors. So, Silicon wafer heavily doped with boron is a p+ substrate.
Q3. 
The impedance looking into nodes 1 and 2 in the given circuit is
Answer : Option A
Explaination / Solution:
Q4. cyclotron frequency of a charged particle having charge q and mass m in a cyclotron producing magnetic field B is
Answer : Option B
Explaination / Solution:
A particle of charge q moving with a speed v on entering a magnetic field B, experiences magnetic Lorentz force which acts as a centripetal force.
here, is the cyclotron frequency.
here, is the cyclotron frequency.
Q5. A battery is connected with a potentiometer wire. The internal resistance of the battery is negligible. If the length of the potentiometer wire of the same material and radius is doubled then
Answer : Option B
Explaination / Solution:
Potential gradient Is given by V/l. If V and l are constant, the potential gradient also remains constant. The change in the radius will cause a change in the current. This does not change the potential gradient.
Q6. 
The approximate transfer characteristic for the circuit shown below with an ideal operational amplifier and diode will be
Answer : Option A
Explaination / Solution:
No Explaination.
Q7. considering the magnetic field of the earth,the correct relation of the geographic pole and the magnetic poles is
Answer : Option A
Explaination / Solution:
No Explaination.
Q8. in n-type semiconductor majority carriers and minority carriers are respectively
Answer : Option B
Explaination / Solution:
N-type semiconductors have a larger electron concentration than hole concentration. The term n-type comes from the negative charge of the electron.
In n-type semiconductors, electrons are the majority carriers and holes are the minority carriers.
N-type semiconductors are created by doping an intrinsic semiconductor with donor impurities (or doping a p-type semiconductor as done in the making of CMOS chips). A common dopant for n-type silicon is phosphorus.
Q9. The truth table
represents the Boolean function
Answer : Option A
Explaination / Solution:
XY'+ XY = X(Y'+ Y) = X
Q10. 
In the figure shown below, the chopper feeds a resistive load from a battery source. MOSFET Q is switched at 250 kHz, with a duty ratio of 0.4. All elements of the circuit are assumed to be ideal
The Peak to Peak source current ripple in amps is
Answer : Option C
Explaination / Solution:
No Explaination.
