All Questions page - 687

A P-type semiconductor has acceptor level 57 meV above the valence band. What is the maximum wavelength of light required to create a hole? (217100 A⁰)

Least paramagnetic property is shown by
Fe
Mn
Ni
Cu

Which of the following gives a red precipitate with AgNO₃ ?

KI

K₂CrO₄

NaBr

NaNO₃ .

How many d electrons are in present Cr²⁺ ion
4
5
6
3

Which one of the following sets correctly represents the increase in the paramagnetic property of ions

Cu⁺²>V⁺²>Cr⁺²>Mn⁺²

Cu⁺²< Cr⁺²< V⁺²< Mn⁺²

Cu⁺²< V⁺²< Cr⁺²< Mn⁺²

V⁺²< Cu⁺²< Cr⁺²< Mn⁺²

What is Dielectric?

What is Dielectric Constant?

Define polarization of a dielectric material.

What are the four polarization mechanisms?

What is the difference between active and passive dielectrics?

List the various breakdown mechanisms in dielectrics.

What is pyro-electricity?

A lead acid battery fitted in a truck develops 24V and has an internal
resistance of 0.01 Ω. It is used to supply current to head lights etc. If the total load is equal to
100 watts, find :
(i) voltage drop in internal resistance
(ii) terminal voltage

A d.c. source generating 500 V has an internal resistance of 1000 Ω. Find the load current if load resistance is
(i) 10 Ω
(ii) 50 Ω
(iii) 100 Ω.

Convert the constant voltage source shown in Fig. 1.16 into constant current source.

Convert the constant current source in Fig. 1.18 into equivalent voltage source

A generator develops 200 V and has an internal resistance of 100 Ω. Find the power delivered to a load of (i) 100 Ω (ii) 300 Ω. Comment on the result.

An audio amplifier produces an alternating output of 12 V before the connection to a load. The amplifier has an equivalent resistance of 15 Ω at the output. What resistance the load need to have to produce maximum power ? Also calculate the power output under this condition.