Electrical Online Test 10

Attempt Free Electrical Online Test 10 Here. Read The Important Electrical MCQ From Below.

1) “The total electric flux through any closed surface surrounding charges is equal to the amount of charge enclosed”. The above statement is associated with

a. Coulomb’s square law
b. Gauss’s law
c. Maxwell’s first law
d. Maxwell’s second law
Ans. b. Gauss’s law

2) The units of capacitance are

a. Volts/coulomb
b. Coulombs/volt
c. Ohms
d. Henry/Wb
Ans. b. Coulombs/volt

3) The electric field at a point situated at a distance d from straight charged conductor is

a. Proportional to d
b. Inversely proportional to d
c. Square inversely proportional to d
d. Square proportional to d
Ans. b. Inversely proportional to d

Electrical Online Test 10

4) The electric field intensity at a point situated 4 meters from a point charge is 200 N/C. If the distance is reduced to 2 meters, the field intensity will be

a. 400 N/C
b. 600 N/C
c. 800 N/C
d. 1600 N/C
Ans. c. 800 N/C

5) Which of the following statement is true ?

a. The current in the discharging capacitor grows linearly
b. The current in the discharging capacitor grows exponentially
c. The current in the discharging capacitor decays exponentially
d. The current in the discharging capacitor decreases constantly
Ans. b. The current in the discharging capacitor grows exponentially

6) The ability of charged bodies to exert force on 6ne another is attributed to the existence of

a. Electrons
b. Protons
c. Neutrons
d. Electric field
Ans. d. Electric field

Electrical Online Test 10

7) The lines of force due to charged particles are

a. Always straight
b. Always curved
c. Sometimes curved
d. None of the above
Ans. b. Always curved

8) Three capacitors each of the capacity C are given. The resultant capacity 2/3 C can be obtained by using them

a. All in series
b. All in parallel
c. Two in parallel and third in series with this combination
d. Two in series and third in parallel across this combination
Ans. c. Two in parallel and third in series with this combination

9) While testing a capacitor with ohm-metre, if the capacitor shows charging, but the final resistance reading is appreciably less than normal, it can be concluded that the capacitor is

a. Short-circuited
b. Open circuited
c. Alright
d. Leaky
Ans. d. Leaky

Electrical Online Test 10

10) An electrolytic capacitor can be used for

a. D.C. only
b. AC. only
c. Both D.C. as well as A.C.
d. D.C. only
Ans. a. D.C. only

11) When 4 volts e.m.f. is applied across a 1 farad capacitor, it will store energy of

a. 2 joules
b. 4 joules
c. 8 joules
d. 16 joules
Ans. c. 8 joules

12) For making a capacitor, it is better to select a dielectric having

a. Low permittivity
b. High permittivity
c. Permittivity same as that of air
d. Permittivity slightly more than that of air
Ans. b. High permittivity

Electrical Online Test 10

13) Voltage applied across a ceramic dielectric produces an electrolytic field 100 times greater than air. What will be the value of dielectric constant ?

a. 50
b. 100
c. 150
d. 200
Ans. b. 100

14) Which of the following statements is correct ?

a. Air capacitors have a black band to indicate the outside foil
b. Electrolytic capacitor must be connected in the correct polarity
c. Ceramic capacitors must be connected in the correct polarity
d. Mica capacitors are available in capacitance value of 1 to 10 pF
Ans. b. Electrolytic capacitor must be connected in the correct polarity

15) A field line and an equipotential surface are

a. Always parallel
b. Always at 90
c. Inclined at any angle 0
d. None of the above
Ans. b. Always at 90

16) For which of the following parameter variation, the capacitance of the capacitor remains unaffected ?

a. Distance between plates
b. Area of the plates
c. Nature of dielectric
d. Thickness of the plates
Ans. d. Thickness of the plates

Electrical Online Test 10

17) The sparking between two electrical contacts can be reduced by inserting a

a. Capacitor in parallel with contacts
b. Capacitor in series with each contact
c. Resistance in line
d. None of the above
Ans. a. Capacitor in parallel with contacts

18) If the sheet of a bakelite is inserted between the plates of an air capacitor, the capacitance will

a. Decrease
b. Increase
c. Remains unchanged
d. Become zero
Ans. b. Increase

19) A capacitor stores 0.24 coulombs at 10 volts. Its capacitance is

a. 0.024 F
b. 0.12 F
c. 0.6 F
d. 0.8 F
Ans. a. 0.024 F

Electrical Online Test 10

20) In a capacitive circuit

a. A steady value of applied voltage causes discharge
b. An increase in applied voltage makes a capacitor charge
c. Decrease in applied voltage makes a capacitor charge
d. None of the above
Ans. b. An increase in applied voltage makes a capacitor charge

21) If A.C. voltage is applied to capacitive circuit, the alternating current can flow in the circuit because

a. Varying voltage produces the charging and discharging currents
b. Of high peak value
c. Charging current can flow
d. Discharge current can flow
Ans. a. Varying voltage produces the charging and discharging currents

Electrical Online Test 10

22) A dielectric material must be

a. Resistor
b. Insulator
c. Good conductor
d. Semi conductor
Ans. b. Insulator

23) Two plates of a parallel plate capacitor after being charged from a constant voltage source are separated apart by means of insulated handles, then the

a. Voltage across the plates increases
b. Voltage across the plates decreases
c. Charge on the capacitor decreases
d. Charge on the capacitor increases
Ans. b. Voltage across the plates decreases

24) If three 10 uF capacitors are connected in parallel, the net capacitance is

a. 10 uF
b. 20 uF
c. 30 uF
d. 40 uF
Ans. c. 30 uF

25) If three 15 uF capacitors are connected in series, the net capacitance is

a. 5 uF
b. 30 uF
c. 45 uF
d. 65 uF

Ans. a. 5 uF

Electrical Online Test 10