Electronics engineering interview question and answer set 1

1. Why we can’t store AC in Batteries instead of DC?

We cannot store AC in batteries because AC changes their polarity upto 50 (When frequency = 50 Hz) or 60 (When frequency = 60 Hz) times in a second. Therefore the battery terminals keep changing Positive (+ve) becomes Negative (-Ve) and vice versa, but the battery cannot change their terminals with the same speed so that’s why we can’t store AC| in Batteries.

Also when we connect a battery with AC Supply, then It will charge during positive half cycle and discharge during negative half cycle because the Positive (+ve) half cycle cancel the negative (-Ve) half cycle, so the average voltage or current in a complete cycle is Zero. So there is no chance to store AC in the Batteries.

Also note that Average Voltage x Average Current ≠Average Power.

2. The Main Difference between Active and passive Components

Active and passive Commonest (Very Easy Explanation with Examples)
Active Components:

Those devices or components which required external source to their operation is called Active Components.
For Example: Diode, Transistors, SCR etc…
Explanation and Example: As we know that Diode is an Active Components. So it is required an External Source to its operation.

Because,  If we connect a Diode in a Circuit and then connect this circuit to the Supply voltage., then Diode will not conduct the current Until the supply voltage reach to 0.3(In case of Germanium) or 0.7V(In case of Silicon). I think you got it

Passive Components:

Those devices or components which do not required external source to their operation is called Passive Components. 
For Example: Resistor, Capacitor, Inductor etc…
Explanation and Example: Passive Components do not require external source to their operation.

Like a Diode, Resistor does not require 0.3 0r 0.7 V. I.e., when we connect a resistor to the supply voltage, it starts work automatically without using a specific voltage. If you understood the above statement about active Components, then you will easily get this example.

In other words:
Active Components:

Those devices or components which produce energy in the form of Voltage or Current are called as Active Components
For Example: Diodes Transistors SCR etc…
Passive Components:

Those devices or components which store or maintain Energy in the form of Voltage or Current are known as Passive Components
For Example:  Resistor, Capacitor, Inductor etc…
In very Simple words;
Active Components: Energy Donor

Passive Components: Energy Acceptor
Also Passive Components are in linear and Active Components are in non linear category.

Electronics engineering interview question and answer set 1