61301. In which of the following semiconductor are holes minority carriers
61302. At 0 K, silicon and germanium behave like monoatomic crystals.
61303. Assertion (A): Acceptor extrinsic semiconductor has higher conductivity than intrinsic semiconductor.Reason (R): Addition of p-type impurity produces an allowable discrete energy level just above valence band.
61304. Soft iron is suitable for making temporary magnets.
61305. Antiferromagnetic materials do not have permanent dipoles.
61306. The Ohm's law for conduction in metals is
61307. The measurement of Hall coefficient of a semiconductor with one type of charge carriers gives the information about
61308. ∈0 has no other physical meaning than that of a fundamental conversion factor.
61309. When temperature is above ferromagnetic Curie temperature, a ferromagnetic material
61310. A magnet does not attract
61311. Bitter powder patterns prove the existence of domains.
61312. Assertion (A): An amorphous material is obtained when mobility of atoms is inhibited during solidification. Reason (R): Crystalline state is a natural state for most solids.
61313. An air cored inductance is a
61314. The number of turns in a coil is doubled. If initial time constant is T, the new time constant is
61315. When a trivalent impurity is added, the semiconductor becomes
61316. Iron has a body centred cubic structure.
61317. The units of polarization of dielectric are
61318. When a potential is applied across an intrinsic semiconductor, holes flow
61319. M = (μr - 1)H.
61320. Silicon and germanium are elements in the
61321. A sample of N type semiconductor has an electron density of 6.25 x 1018/cm3 at 300 K. If intrinsic concentration of carriers in this sample is 2.5 x 1013/cm3 at this temperature, the hole density is
61322. Assertion (A): In a conductor, current density remains constant in time as long as E is constant.Reason (R): In a conductor, J = σE.
61323. A specimen of metal has n valence electrons per m3. If vx is the average velocity of these electrons, each having a charge e, the current density J is
61324. Which of the following is used in temperature alarm circuits?
61325. Which European Country gifted the statue of liberty to the United States?
61326. n type semiconductors
61327. The most important primary force of attraction in the formation of solids is
61328. When two conductors carry currents in the same direction the force is repulsive.
61329. The dielectric losses do not depend on frequency.
61330. Assertion (A): Holes are majority carriers in p type semiconductor.Reason (R): In p type semiconductor, the electrons produced by thermal agitation recombine with holes.
61331. If t is relaxation time and t c is average time between collisions, then in an isotropic metal
61332. Assertion (A): Resistivity of a perfect single crystal of a metal goes to zero as T approaches zero.Reason (R): Scattering of electrons is due to deviations from perfect periodicity of lattice.
61333. Fleming's left hand rule is used to find
61334. After the decline of the Guptas, a large part of North India was reunited by?
61335. The rule that resistivity of conductors can be separated into two parts viz. temperature independent and temperature dependent is known as
61336. Above a certain temperature, the specific heat of a metal becomes constant. This temperature is called
61337. A dielectric material must be
61338. Spontaneous magnetisation is characteristic of ferromagnetic materials.
61339. Assertion (A): The angular momentum of an atom is due to three contributions viz. orbital, electron spin and nuclear spin.Reason (R): The nuclear spin magnetic moment is much more than electron spin magnetic moment.
61340. If WF is the Fermi level, then in a metal at T = 0
61341. Silicon and germanium have diamond structure. The number of atoms in a volume equal to a3 where a is the edge of elementary cube are
61342. If the radius of electron cloud around the nucleus of a rare gas atom is R, the electronic polarizability of the atom is porportional to
61343. By inserting a plate of dielectric between the plates of a parallel plate capacitor, the energy stored in the capacitor is increased five times. The dielectric constant of material is
61344. Assertion (A): A capacitor with imperfect dielectric can be represented by a capacitance in parallel with resistance.Reason (R): For imperfect dielectrics, dielectric constant has real and imaginary parts.
61345. An atom of a rare gas is placed is an electric field E. Then
61346. In van der walls crystals, there exists a high degree of stability of the outer electron shell.
61347. As per temperature limits, the number of categories of solid dielectrics are
61348. At room temperature the number of conducting electrons in an intrinsic semiconductor
61349. A characteristic property of crystal is its periodicity of structure.
61350. If Bmax is the maximum flux density, hysteresis loss is proportional to