EE8392 ELECTROMAGNETIC THEORY INTERNAL 2

The capacitance of a material refers to

• Ability of the material to store magnetic field

• Ability of the material to store electromagnetic field

• Ability of the material to store electric field

• Potential between two charged plates

The capacitance of a capacitor is not affected by

• distance between the plates

• area of the plates

• thickness between the plates

• all the above

Find the time constant in a series R-L circuit when the resistance is 4 ohm and the inductance is 2 H.

• 0.25

• 0.2

• 2

• 0.5

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

• decrease

• increase

• remains unchanged

• become zero

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

• 0.24 F

• 0.12 F

• 0.6 F

• 0.8 F

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

• low permittivity

• high permittivity

• permittivity same as that of air

• permittivity slightly more than that of air

If three 15 microfarad capacitors are connected in series, the net capacitance is

• 5 microfarad

• 30 microfarad

• 45 microfarad

• 50 microfarad

An electrolytic capacitor can be used for

• D.C. only

• AC. only

• both D.C. as well as A.C

• a alone

Calculate the capacitance of two parallel plates of area 2 units separated by a distance of 0.2m in air(in picofarad)

• 8.84

• 88.4

• 884.1

• 0.884

A infinite resistance is considered as a/an

• Closed path(short circuit)

• Open path

• Not defined

• Ammeter with zero reading