A degaussing is the process of removing gases from materials. demagnetising metallic parts. remagnetising metallic parts. removal of magnetic impurities. TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following gives materials in order of decreasing values of permeability? Silver, copper, aluminium, iron. Pure iron, silicon iron, aluminium, bismuth. Permalloy, nickel, air, water. Cobalt, nickel, aluminium, iron. TRUE ANSWER : ? YOUR ANSWER : ?
The dielectric strength of ferroelectric materials depends to a large extent on presence of magnetic materials in the vicinity. frequency of applied voltage. area of hysteresis loop for the material. intensity of electric field. TRUE ANSWER : ? YOUR ANSWER : ?
In order to minimise loss due to hysteresis, the magnetic material should have low hysteresis coefficient. large B-H loop area. high resistivity. high retentivity. TRUE ANSWER : ? YOUR ANSWER : ?
The temperature beyond which substances lose their ferroelectric properties, is known as inversion temperature. critical temperature. curie temperature. conversion temperature. TRUE ANSWER : ? YOUR ANSWER : ?
Which statement is not true of ferromagnetic materials. They lose their nonlinearly property above the Curie temperature. They have fixed value of μr. Energy loss is proportional to the area of hysteresis loop. They have large magnetic susceptibility. TRUE ANSWER : ? YOUR ANSWER : ?
Temporary magnets are used in which of the following ? Hoist. Generators. All of these. Motors. TRUE ANSWER : ? YOUR ANSWER : ?
The electron configuration of copper is 1s2 , 2s2 2p6, 3s2 3p6 3d10, 4s1. none of above. 1s2 , 2s2 2p6, 3s2 3p6 3d9, 4s2. 1s2 , 2s2 2p6, 3s2 3p6 3d8, 4s1 4p TRUE ANSWER : ? YOUR ANSWER : ?
The intensity of magnetization, M, of a ferro magnetic solid increases with increasing temperature. depends on method of heating. decreases with increasing temperature. is independent of temperature. TRUE ANSWER : ? YOUR ANSWER : ?
A ferromagnetic core subjected to cycles of magnetisation will exhibit hysteresis when the cycle is / >(A), (B), and (C) are all correct. alternating. pulsating. rotating. TRUE ANSWER : ? YOUR ANSWER : ?