Materials and Components

1.Which capacitor-store higher amount of energy?
Air capacitor Paper capacitor Mica capacitor Plastic film capacitor

2.In paramagnetic materials
permanent magnetic dipoles exist but the interaction between neighbouring dipoles is negligible permanent magnetic dipole do not exist permanent magnetic dipoles exist and the interaction between neighbouring dipoles is very strong permanent magnetic dipole moment may or may not exist

3.The core of a coil has a length of 10 cm. The self inductance is 8 mH. If the core length is doubled, all other quantities remaining the same, the self inductance will be
32 mH 16 mH 8 mH 4 mH

4.Two materials having temperature coefficients of 0.004 and 0.0004 respectively are joined in series. The overall temperature coefficient is likely to be
0.08 0.04 0.001 0.0001

5.The number of valence electrons in pentavalent impurity is
5 4 3 1


6.If the diameter of a wire is doubled, its current carrying capacity becomes
one-fourth half twice four times

7.Material which lack permanent magnetic dipoles are known as
paramagnetic diamagnetic ferromagnetic ferrimagnetic

8.A parallel plate capacitor has its length, width and separation doubled. It fringing effects are neglected, to keep the capacitance same, the dielectric constant must be
halved kept the same doubled made 4 times

9.When an electric field E is applied to solid and liquid insulating materials, the internal field Ei acting at the location of atom is such that
Ei = E Ei > E Ei < E Ei may be equal to or less than E

10.Which element exhibits the property of inertia?
Resistance Capacitance Inductance Both resistance and inductance