Home » Electrical Engineering » Electrical Engineering MCQ » Electrostatics and Capacitance

### 1.The force between two charges is 120 N. if the distance between the charges is doubled, the force will be

• A60 N
• B30 N
• C40 N
• D20 N

30 N

Explanation:

The force between two charges is 120 N. if the distance between the charges is doubled, the force will be 30 N.

• A400 N/C
• B600 N/C
• C800 N/C
• D1200 N/C

800 N/C

Explanation:

### 3.The lines of force due to charge particles are

• AAlways straight
• BAlways curved
• CSometimes curved
• DNone of the above

Always curved

Explanation:

The lines of force due to charge particles are Always curved.

### 4.The electric field at a point situated at a distance d from straight charged conductor is

• AProportional to d
• BInversely proportional to d
• CInversely proportional to square of distance
• DNone of the above

Inversely proportional to d

Explanation:

The electric field at a point situated at a distance d from straight charged conductor is Inversely proportional to d.

### 5.The direction of electric field due to positive charge is

• AAway from the charge
• BTowards the charge
• CBoth (a) and (b)
• DNone of the above

Away from the charge

Explanation:

The direction of electric field due to positive charge is Away from the charge.

### 6.A field line and an equipotential surface are

• AAlways parallel
• BAlways at 90°
• CInclined at any angle
• DNone of the above

Always at 90°

Explanation:

A field line and an equipotential surface are Always at 90?

### 7.The ability of charged bodies to exert force on one another is attributed to the existence of

• AElectrons
• BProtons
• CNeutrons
• DElectric field

Electric field

Explanation:

The ability of charged bodies to exert force on one another is attributed to the existence of Electric field.

### 8.If the sheet of a Bakelite is inserted between plates of an air capacitor, the capacitance will

• Bincrease
• Cremain unchanged
• Dbecome zero

increase

Explanation:

If the sheet of a Bakelite is inserted between plates of an air capacitor, the capacitance will increase.

### 9.A capacitor stores 0.24 coulombs at 10 volts. Its capacitance is

• A0.024 F
• B0.12 F
• C0.6 F
• D0.8 F

0.024 F

Explanation:

A capacitor stores 0.24 coulombs at 10 volts. Its capacitance is 0.024 F.

### 10.For making a capacitor, it is better to select a dielectric having

• ALow permittivity
• BHigh permittivity
• CPermittivity same as that of air
• DPermittivity slightly more than that of air

High permittivity

Explanation:

For making a capacitor, it is better to select a dielectric having High permittivity.

### 11.The units of capacitance are

• AVolts/coulombs
• BCoulombs/volts
• COhms
• DHennery/wb

Coulombs/volts

Explanation:

The units of capacitance are Coulombs/volts.

### 12.The unit of capacitance is

• AHennery
• BOhm

Hennery

Explanation:

The unit of capacitance is Farad.

### 13.A dielectric material must be

• AResistor
• BInsulator
• CGood conductor
• DSemi-conductor

Insulator

Explanation:

A dielectric material must be Insulator.

### 14.The electrolytic capacitor can be used for

• BAC only
• CBoth DC as well as AC
• DNone of these

DC only

Explanation:

The electrolytic capacitor can be used for DC only.

### 15.The capacitance of a capacitor is not affected by

• BArea of plates
• CThickness of plates
• DAll of the above

Thickness of plates

Explanation:

The capacitance of a capacitor is not affected by Thickness of plates.

### 16.Which of the following is not a vector?

• ALinear momentum
• BAngular momentum
• CElectric field
• DElectric potential

Electric potential

Explanation:

• A4
• B2
• C?
• D?

2

Explanation:

### 18.Electric field inside a hollow metallic charged sphere is

• AIncreasing towards centre
• BDecreasing towards centre
• CZero
• DNone of the above

Zero

Explanation:

Electric field inside a hollow metallic charged sphere is Zero.

### 19.Two plates of parallel plate capacitor after being charges from a constant voltage source is separated apart by means of insulated handles, then the

• AVoltage across the plates increases
• BVoltage across the plate decreases
• CCharge on the capacitor decreases
• DCharge on the capacitor increases

Voltage across the plate decreases

Explanation:

### 20.If AC voltage is applied to capacitive circuit, the alternating current can be flow in the circuit because

• AVarying voltage produces the charging and discharging currents
• BOf high peak value
• CCharging current can flow
• DDischarge current can flow