Last Answer : Addition of trivalent impurity to a semiconductor creates many Holes.
Description : In order to obtain p-type germanium it should be doped with a (A) Trivalent impurity. (B) Tetravalent impurity. (C) Pentavalent impurity. (D) Any of the above will do.
Last Answer : (A) Trivalent impurity.
Description : In n type semi conductor added impurity is (A) pentavalent. (B) divalent. (C) tetravalent. (D) trivalent.
Last Answer : (A) pentavalent.
Description : In p-type semiconductor the majority carriers are (A) holes. (B) electrons. (C) positive ions. (D) negative ions.
Last Answer : (A) holes.
Description : A semiconductor formed by addition of trivalent impurity is : a) P–Type b) N–Type c) Q–type d) M–Type
Last Answer : d) M–Type
Description : When a semiconductor is doped with a P-type impurity, each impurity atom will (A) acquire negative charge. (B) acquire positive charge. (C) remain electrically neutral. (D) give away one electron.
Last Answer : (A) acquire negative charge.
Last Answer : Addition of pentavalent impurity to a semiconductor creates many Free electrons.
Description : Barrier potential in a P-N junction is caused by (A) Thermally generated electrons and holes. (B) Diffusion of majority carriers across the junction. (C) Migration of minority carriers across the junction. (D) Flow of drift current.
Last Answer : (B) Diffusion of majority carriers across the junction.
Last Answer : A trivalent impurity has 3 valence electrons.
Description : The conductivity of an extrinsic semiconductor (A) decreases with temperature. (B) increases with temperature. (C) remains constant with temperature. (D) decreases and then increases with temperature.
Last Answer : (B) increases with temperature.
Description : A pure semiconductor under ordinary conditions behaves like (A) a conductor. (B) an insulator. (C) a magnetic material. (D) a ferro-electric material.
Last Answer : (B) an insulator.
Description : Hall effect may be used for which of the following? (A) determining whether the semiconductor is p or n type. (B) determining the carrier concentration. (C) calculating the mobility. (D) All the above.
Last Answer : (D) All the above. Ans: D Determining whether the semiconductor is p or n type, determining the carrier concentration, calculating the mobility
Description : n-type semiconductor is an example of (A) extrinsic semiconductor. (B) intrinsic semiconductor. (C) super conductor. (D) insulators..
Last Answer : (A) extrinsic semiconductor.
Description : The electrons in the outermost orbit of atom are: a) Valance electrons b) Static electrons c) Tightly bound d) Stationary
Last Answer : a) Valance electrons
Description : C and Si both have same lattice structure, having 4 bonding electrons in each. However, C is insulator where as Si is intrinsic semiconductor. This is because (1) The four bonding electrons in the case of C ... the case of C lie in the second orbit, whereas in the case of Si they lie in the third
Last Answer : (4) The four bonding electrons in the case of C lie in the second orbit, whereas in the case of Si they lie in the third
Description : Holes are majority carriers in (A) P-type semiconductors. (B) N-type semiconductors. (C) Insulators. (D) Superconductors.
Last Answer : (A) P-type semiconductors.
Description : Atoms with four valence electrons are good conductors. (A) True (B) False
Last Answer : (B) False
Description : Germanium possesses (A) one valence electrons. (B) two valence electrons. (C) three valence electrons. (D) four valence electrons.
Last Answer : (D) four valence electrons.
Description : All semiconductors in their last orbit have (A) 8 electrons. (B) 2 electrons. (C) 4 electrons. (D) 6 electrons.
Last Answer : (C) 4 electrons.
Description : Atomic weight of an atom is (A) sum of the number of protons and neutrons. (B) sum of the number of protons and electrons. (C) sum of the number of electrons and neutrons. (D) sum of the number of electrons, protons and neutrons.
Last Answer : (A) sum of the number of protons and neutrons.
Description : The process of addition of impurity in pure semiconductor is : a) Doping b) Radiating c) Mixing d) Insulating
Last Answer : d) Insulating
Description : Semiconductor germanium and silicon are (a) Pentavalent (b) trivalent (c) divalent (d) tetravalent
Last Answer : (d) tetravalent
Description : Fire refining process is employed in case of (A) Tin (B) Copper (C) Zinc (D) Aluminium
Last Answer : (B) Copper
Description : What is the name given to a piece of pure semiconductor material that has an equal number of electrons and holes?
Last Answer : Intrinsic.
Description : The reverse current through semiconductor diode is due to (a) Minority carrier (b) majority carrier (c) electrons (d) holes
Last Answer : (a) Minority carrier
Description : In the N-type semiconductor the charge carries are a) Holes b) Neutrons c) Protons d) Electrons
Last Answer : d) Electrons
Description : In a P-type semiconductor the charge carriers are a) Electrons b) Holes c) Protons d) Neutrons
Last Answer : b) Holes
Description : A P-type semiconductor is doped to produce one of the following. Will it produce: w) both holes and electrons x) positive electrons y) negative electrons z) holes
Last Answer : ANSWER: Z -- HOLES
Description : The following type of bonding is strongly directional in solids. (A) Vander Waal's (B) Ionic (C) Metallic (D) Covalent
Last Answer : D) Covalent
Description : What is a modular system? List the important properties of a modular system.
Last Answer : Ans: A modular system consists of well defined manageable units to well defined interfaces among them. Desirable properties are Each module is a well defined subsystem useful to others Each module ... modules Modules should be easier to use than build Modules should have a simple interface
Description : State the functions of a fuse. Mention the desirable properties of fuse materials.
Last Answer : Ans: Fuse is a protective device, which consists of a thin wire or strip. This wire or strip is placed with the circuit it has to protect, so that the circuit-current flows through it. When ... silver and silver alloys are used of lower ratings. Copper alloys are used in fuses of higher ratings.
Description : Give four examples of natural insulating materials.
Last Answer : Ans: Examples of the natural insulating materials are cotton, rubber, wood, mica.
Description : Classify plastic materials into two categories, describe their important properties and give two examples of each.
Last Answer : Ans: Plastic materials can be classified into thermoplastic and thermosetting plastics. Thermoplastic materials:- The properties of these plastic materials do not change considerably if they are melted ... forming elastic threads and films. Examples are Phenol formaldehyde (Bakelite), Epoxy resins.
Description : Ferroelectric materials are characterised by (A) Very high degree of polarisation. (B) A sharp dependence of polarisation on temperature. (C) Non-linear dependence of the charge Q on the applied voltage. (D) All the above.
Last Answer : (D) All the above.
Description : Tick of the property, which is different from the group (A) Ductility. (B) Resistivity. (C) Tensile strength. (D) Hardness.
Last Answer : (B) Resistivity
Description : Tick off the material, which is different from the group (A) Constantan. (B) Manganin. (C) Nichrome. (D) Brass.
Last Answer : (D) Brass.
Description : Semi-conductors have ________ temperature coefficient of resistance. (A) Negative (B) Positive (C) Both positive and negative (D) None of the above
Last Answer : (A) Negative
Description : Hysteresis loss least depends on (A) Frequency. (B) Magnetic field intensity. (C) Volume of the material. (D) Grain orientation of material.
Last Answer : (D) Grain orientation of material.
Description : Insulators have (A) A full valence band. (B) An empty conduction band. (C) A large energy gap. (D) All the above.
Last Answer : (C) A large energy gap.
Description : Paper is hygroscopic and absorbent. (A) True (B) False
Last Answer : (A) True
Description : In a ferromagnetic material the state of flux density is as follows when external magnetic field is applied to it. (A) Increased (B) Decreased (C) Remains unchanged (D) Becomes zero
Last Answer : (C) Remains unchanged
Description : Magnetic materials (A) provide path to magnetic flux. (B) are good insulators. (C) are semiconductors. (D) None.
Last Answer : (A) provide path to magnetic flux.
Description : Hall effect is associated with (A) Conductors. (B) Semiconductors. (C) Thermistors. (D) Solders.
Last Answer : (B) Semiconductors.
Description : Hard magnetic materials are used for making (A) Permanent magnets. (B) Temporary magnets. (C) Conductors. (D) Insulator.
Last Answer : (A) Permanent magnets.
Description : Example of high resistivity material is (A) Nichrome (B) Silver (C) Gold (D) Copper
Last Answer : (A) Nichrome
Description : A transistor has (A) One p-n junction. (B) Two p-n junction. (C) Four p-n junction. (D) Five p-n junction.
Last Answer : (B) Two p-n junction.
Description : Bronze is an alloy of (A) Copper and Tin. (B) Copper and Steel. (C) Copper and Mercury. (D) Copper and Aluminium.
Last Answer : (A) Copper and Tin.
Description : Which of the following material has the highest melting point (A) Copper. (B) Aluminium. (C) Tungsten. (D) Gold.
Last Answer : (C) Tungsten.
Description : Number of Terminals in a MOSFET are (A) Two (B) Three (C) Four (D) Five
Last Answer : (B) Three
Description : P-N junction is (A) a rectifier. (B) an amplifier. (C) an Oscillator. (D) a Coupler.
Last Answer : (A) a rectifier.