Soft iron is suitable for making temporary magnets.

More Questions from Materials and Components

• 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
• A metal has a large number of free electrons. If e is electronic charge and m is mass of electron and an electric field E is applied along (say) x direction, the electrons acquire a velocity having a component vx is x direction. Then
• If the operating temperature increases by 10°C, the rate of deterioration of solid dielectric becomes
• The measurement of Hall coefficient of a semiconductor with one type of charge carriers gives the information about
• When two conductors carry currents in the same direction the force is repulsive.
• When a trivalent impurity is added, the semiconductor becomes
• For dielectrics in alternating field, polarizability ae is a complex quantity. The imaginary part of ae is zero for
• Bitter powder patterns prove the existence of domains.
• Assertion (A): If an electron having charge e is revolving in an orbit of radius R and with angular velocity ω, the magnetic dipole moment of orbit is 0.5 eωR2. Reason (R): Orbital angular momentum and magnetic dipole moment are always equal.
• For making a capacitor it is better to have a dielectric having

Discussion & Comments