61251. Magnetic hysteresis phenomenon is explained by
61252. The function of haemoglobin is?
61253. The relation between thermal conductivity K (W/m/°C), heat flow density Q (watt/m2) and dT/dx (°C per metre) is
61254. As per Matthiessen's rule, the total resistivity r of a conductor can be written as r = r i + aT, where r i and a are constants and T is absolute temperature. At very low temperatures
61255. Consider the following statement: In case of a superconductor B = 0μr is highdiamagnetism is hightransition temperature varies with isotopic mass. Of the above statements
61256. Assertion (A): In liquids and glassy substances, dielectric losses occur. Reason (R): The orientation polarization in many substances is frequency dependent.
61257. A single layer air cored coil has n turns and inductance L. If a new coil is formed by having 2n turns while keeping the coil length and diameter the same, the new inductance is
61258. The colour code on a carbon resistor is yellow-violet-orange. The value of resistance is
61259. A dielectric of relative permittivity ∈r is subjected to a homogeneous electric field E. The dipole moment P per unit volume is given by
61260. Which of these has the highest dielectric strength?
61261. An electron in a metal suffers collision and if the probability of it being scattered over an angle dθ is 2p P(θ) sin θ dθ where P(θ) is an arbitrary function of scattering angle θ, then
61262. For an insulating material, dielectric strength and dielectric losses should be
61263. Consider the following statements An iron cored choke is non linear and passive device.A carbon resistor kept in sunlight is a time invariant and passive device.A dry cell is a time varying and active device.An air capacitor is time invariant and passive device. Of these statements
61264. Some ceramic materials become superconducting
61265. Assertion (A): Doping level in extrinsic semiconductors is very small.Reason (R): Additional of impurity in the ratio of 1 part in 108 parts increases the number of charge carriers by about 20.
61266. The core of an atom consists of
61267. Assertion (A): Copper is a good conductor of electricity.Reason (R): Copper has a face centred cubic lattice.
61268. When a dielectric is subjected to an electric field E, each volume element of dielectric can be considered to be carrying an electric dipole moment.
61269. Assertion (A): In an intrinsic semiconductor J = (μn x μp)eni.Reason (R): Intrinsic charge concentration ni at temperature T is given by ni2 = A0 T3 e-EG0/kT.
61270. When the atom of rare gas is placed in an electric field the nucleus shifts from the centre of electron cloud by an amount x. If the radius of electron cloud is R, then
61271. Macroscopic quantities of a given material
61272. For a superconductor, the relative permeability is
61273. The relative permeability of a ferromagnetic material is
61274. The direction of trade winds in the northern hemisphere?
61275. Assertion (A): The equation D = ∈0∈rE is applicable only to isotropic materials.Reason (R): In polycrystalline materials, the directional effects are absent.
61276. Assertion (A): For a dielectric, P = ∈0(∈r - 1) E.Reason (R): Dipole moment per unit volume is called polarization of dielectric.
61277. Assertion (A): Ferrites are very useful at very high frequencies.Reason (R): Ferrites have high permeability and high resistivity.
61278. In a conductor the current flow is due to
61279. When an electron moves at velocity v in combined electric and magnetic fields E and H, the Lorentz force F is F = - e(E + v x B).
61280. Anuja Prakash Thaku is related with which of the following game?
61281. When Schrodinger equation is applied to the motion of electron in the field of protons, the physically acceptable solutions for the wave function exist for quantum number which are
61282. For dielectrics in alternating field, polarizability a e is a complex quantity. The imaginary part of a e is zero for
61283. In the wave mechanical theory, the maximum of the charge distribution in the ground state occurs for a distance from the nucleus equal to
61284. Hysteresis curve is associated with motion of domain walls.
61285. The number of protons in germanium atom is
61286. Sulphur hexafluoride is used in
61287. The number of valence electrons in trivalent impurity is
61288. The v-i characteristic shown in the given figure is for
61289. The induced magnetic dipole moment has a direction opposite to the applied magnetic field.
61290. An atom of polarizability a is placed in a homogeneous electric field E. The energy stored in polarized atom is
61291. If B, H and M denote flux density, field intensity and magnetisation, B = μ0 (H + M).
61292. A capacitor can be represented by a capacitance and resistance in parallel. For a good capacitor, this parallel resistance should be
61293. Assertion (A): Ionic solids, in general, have no electrical conductivity.Reason (R): In ionic solids, electrons are tightly bound to the nucleus.
61294. The number of players in a basket ball team?
61295. The number of valence electrons in silicon atom is
61296. ∈r is determined by the atomic structure of the dielectric.
61297. A rare gas has N atoms per m3. If electronic polarizability of single atom of this gas is a e, then
61298. The colour code on a carbon resistor is brown-black-red-gold. The value of resistance is
61299. Tesla is a unit of
61300. If the operating temperature increases by 10°C, the rate of deterioration of solid dielectric becomes