**SSC JE Electrical Important MCQ PDF Part 11**

1.If the forward anode current of a thyristor is reduced below its holding current then the thyristor remains in _____________.

A. ON state

B. OFF State

C. Blocking State

D. Reverse State

Answer : C

2.The minimum anode current to maintain the thyristor in on state is __________.

A. Holding Current

B. Latching Current

C. Reverse Current

D. Reserve Current

Answer : A

3.The number of lumens emitted by the source per unit solid angle is ____________.

A. Lumen

B. Candle Power

C. Luminous Intensity

D. Brightness

Answer : B

4.Determine the distance for a 25 c.p lamp from a normally placed screen in order that the illumination shall be 5 lux.

A. 2M

B. 2.24M

C. 3.5M

D. 4.2M

Answer : B (Illumination=Candle Power/(Distance)² So (Distance)² =Candle Power/Illumination=25/5=5 or Distance=√5=2.24 M)

5. If αdc = 0.98 then βdc is _____.

A. 0.49

B. 49

C. 0.59

D. 59

Answer : B (β = ɑ/(1 – ɑ) =0.98/(1 – 0.98)=49)

6.What is the emf equation of a transformer

A. E₂/E₁=N₂/N₁

B. E₁/E₂=N₂/N₁

C. E₂/E₁=N₁/N₂

D. E₁E₂=N₁N₂

Answer : A

7.In a transformer which of the following does not change

A. Voltage

B. Current

C. Frequency

D. Power

Answer : C

8.What is the binary equivalent of decimal 14

A. 1400

B. 1110

C. 0014

D. 1101

Answer : B

(Step 1: Divide (14)_{10} successively by 2 until the quotient is 0:

14/2 = 7, remainder is 0

7/2 = 3, remainder is 1

3/2 = 1, remainder is 1

1/2 = 0, remainder is 1

Step 2: Read from the bottom (MSB) to top (LSB) as 1110.

So, 1110 is the binary equivalent of decimal number 14)

9.What is the current gain of Common Collector configuration

A. Ic/Ib

B. Ic/Ie

C. Ie/Ib

D. Ie/Ic

Answer : C (The current amplification factor is defined as the ratio of the output current to the input current. In common emitter configuration, the output current is emitter current I_{E}, whereas the input current is base current I_{B)}

10.The point where DC load line and forward characteristic intersect is

A. Origin Point

B. Quiescent Point

C. X intersect Point

D. Y intersect Point

Answer : B

11.If Input and Output junctions of a transistor are forward biased, then the region of operation is __________.

A. Active

B. Saturated

C. Cut off

D. Inverted

Answer : B

12.The relation between Magnetic Field Intensity and Magnetic Flux Density is ________

A. B = μH

B. H = μB

C. μ = BH

D. μHB = 1

Answer : A

13.Which of the following is a donor impurity element to form a N type semiconductor

A. Boron

B. Aluminum

C. Phosphorous

D. Gallium

Answer : C ( Donor impurity -phosphorus, arsenic, antimony, bismuth )

14.If the width of forbidden gap between valence and conduction band is very large, then the material is ______________.

A. Conductor

B. Insulator

C. Semi-conductor

D. Solid

Answer : B

15.The current Io of Figure is

A. – 4 A

B. -2 A

C. 4 A

D. 16 A

Answer : A (Io+10=2+4 or Io=6-10=-4)

16.One kWh of electrical energy equals

A. 3600 J

B. 860 kcal

C. 3600 W

D. 4186 J

Answer : B

(1 kwh = 3.6 mega joules

1 mega joules= 239005.74 calories

3.6 mega joules = 860420.65 calories.

1 kwh = 860420.65 calories=860 kcal)

17.The effect of connecting an additional parallel load to an electrical supply source is to increase the

A. Resistance of the load

B. Voltage of the source

C. Current taken from the source

D. P.D. across the load

Answer : C

18.A 10 Ω resistor is connected in parallel with a 15 Ω resistor and the combination in series with a 12 Ω resistor. The equivalent resistance of the circuit is

A. 37 Ω

B. 18 Ω

C. 27 Ω

D. 4 Ω

Answer : B (R Parallel=10*15/25=6 Total R=6+12=18 Ω)

19.Flux in a magnetic circuit is analogous to

A. Voltage in an electric circuit

B. Current in an electric circuit

C. Power in an electric circuit

D. Resistance in an electric circuit

Answer : B

20.Faraday’s laws of electromagnetic induction are related to

A. The e.m.f. of a chemical cell

B. The e.m.f. of a generator

C. The current flowing in a conductor

D. The strength of a magnetic field

Answer : B