# Basic Concepts (MCQs With Explanatory Answers)

## **Basic Concepts (Electrical Fundamentals) MCQs With Explanatory Answers **

*1. What is The Basic Three Electrical Quantities. *

- Resistance, Capacitance, Inductance
- Power, Voltage, Conductance
- Voltage, Current, Resistance(Impedance)
- Current , Reluctance, Inductance

### Show Explanatory Answer

*Answer: 3. Voltage, Current, Resistance (Impedance)***Explanation:** The reader may select option 1, but do not forget that there is no concept of Option 1 ( Resistance, Capacitance , inductance ) without Option 3 ( Voltage, Current, Power ) Hence The basic Electrical Quantities are Voltage, Current and Power ( Option 3).

*2. In case of Short Circuit,_______Current will flow in the Circuit. *

- Zero.
- Very Low
- Normal.
- Infinite

### Show Explanatory Answer

*Answer: 4. Infinite***Explanation:** At the short circuited point, the voltage difference is very low (about Zero) So then put the value in → I = P/V …. so if we put V = 0, Then Current will be infinite.

** 3. Ω (Ohm) is the Unit of ___________?**

- Resistance (R)
- Inductive Reactance ( X
_{L}) - Capacitive Reactance (Xc)
- All of the above
- None of the above

### Show Explanatory Answer

*Answer: 4. All of the above***Explanation:** As we better know that Inductive and Capacitive reactances are resistances, so the unit of all these quantities should be same i.e Ohm (Ω)

*4. Siemens or Mho (**℧**) is the unit of ____________?*

- Conductance
- Admittance
- Both 1 & 2
- None of the above

### Show Explanatory Answer

*Answer: 3. Both 1 & 2.***Explanation:** Conductance (G) is the inverse/reciprocal of Resistance (R) and the SI unit of Conductance (G) is Siemens (S) or Mho (℧) and Admittance (Y) is the inverse/reciprocal of Impedance(Z). but we also know that impedance(Z) is resistance in AC Circuits. So both of (R) and (Z) are Resistances. Therefore the reciprocal/inverse of R and Z = G and Y respectively. And G and Y are same. So the SI unit of these Quantities ( G and Y ) = Siemens (S) or (or Mho (℧).

*5. What quantity of charge must be delivered by a battery with a Potential Difference of 110 V to do 660J of Work?*

- 0.6 C
- 6 C
- 60 C
- 600 C

### Show Explanatory Answer

**Answer: 2. 6C**

**Explanation: ** Q = W / V = 660J / 110V = **6C**

**6. The quantity of a charge that will be transferred by a current flow of 10 A over 1 hour period is_________ ?**

- 10 C
- 3.6 x 10
^{4}C - 2.4 x 10
^{3}C - 1.6 x 10
^{2}C

### Show Explanatory Answer

**Answer: 2. 3.6 x 10**

^{4}C**Explanation:** Q = I x t = 10A x ( 60 x 60 Sec) = **3.6 x 10 ^{4} C**

* 7. If a 100Watts Bulbs ON for 10 hours, then what will be the amount of consumed Electricity? *

- 100Watts
- 100Watts per Hour
- 1000 Watts ( 1kW)
- 1kWh = 1 Unit of electricity

### Show Explanatory Answer

**Answer:**

*4. 1kWh = 1 Unit of Electricity.***Explanation: **The Basic Unit for Consumed Electricity is kWh = one unit (also Called Board of Trade Unit =BTU). Now, 10 hours x 100 Watts = 1kWh. (1kW = 1000Watts.

why ac ratings are in tons?

its all about BTU i.e british thermal units BTU: energy required to raise the temp of room by a degree 1 ton=12000 BTU/hr

because initially people use ice to decrease the temperature and ice required in tons that’s why 1 ton ac cooling power equal to 1 ton of ice cooling power

misplaced answer on question 3

Thanks 4 correction

Helpful common electrical knowledge. Thanks……..

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Thank You.

The Basic Unit for Consumed Electricity is kWh = one unit (also Called Board of Trade Unit =BTU).

Now, 10 hours x 100 Hours = 1kWh. Watts = 1000Watts.

how to get 100 hours???

Thanks For correction… It was 10 Hours x 100Watss = 1000Wh = 1kW.

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Plz open in answer

Hi Amit… Just Click on “Expand Explanatory Answer”.

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