Description : Solids which conduct electricity at higher temperature but not at lower temperature are called (1) super-conductor (2) metallic-conductor (3) semi-conductor (4) insulator
Last Answer : (3) semi-conductor Explanation: Semiconductors are insulators at low temperatures and reasonably good conductors at higher temperatures. As temperature increases, the semiconductor material becomes a better and better conductor.
Description : At low temperature, Lead behaves as a (1) Semi conductor (2) Super conductor (3) Insulator (4) Conductor
Last Answer : (2) Super conductor Explanation: Lead exhibit superconducting phase transitions at low temperatures of 7.2 Kelvin. This discovery was made in 1913. At this temperature (known as critical temperature), ... to a different phase of matter; this superconducting phase is described by the BCS theory.
Last Answer : (2) Super conductor Explanation: Lead exhibit super conducting phase transitions at low temperatures of 7.2 Kelvin. This discovery was made in 1913.
Description : At low temperature, Lead behaves as a : (1) Semi conductor (2) Super conductor (3) Insulator (4) Conductor
Last Answer : Super conductor
Description : Metalloids (A) Are good conductor of heat & electricity (B) Act as electron donors with metals & as electron acceptor with non metals (C) Are not necessarily solids at room temperature ... & non-metallic properties to some extent and are exemplified by elements like germanium, silicon & boron
Last Answer : D) Are compounds that exhibit both metallic & non-metallic properties to some extent and are exemplified by elements like germanium, silicon & boron
Description : Some substances are good conductor of electricity in both the solid and liquid states. These substances are generally-------? A. ionic substances B. metallic substances (Answer) C. molecular solids D. covalent network solids
Last Answer : B. metallic substances (Answer)
Description : The electrode for a battery must be A. A semi conductor B. An insulator C. A good conductor of electricity D. A bad conductor of electricity
Last Answer : C. A good conductor of electricity
Description : Ceramic compounds as compared to metallic compounds (A) Crystallise faster (B) Resist greater tensile stress at room temperature (C) Have higher melting temperature (D) Are better conductor of electricity at higher temperature
Last Answer : Option C
Description : Ohm’s law obeyed in - (1) a metallic conductor (2) a semi conductor (3) an electron tube (4) in all of the above
Last Answer : (1) a metallic conductor Explanation: There are, however, components of electrical circuits which do not obey Ohm's law; that is, their relationship between current and voltage (their I–V curve) is nonlinear (or non-ohmic).
Description : Superconductors are those elements – (1) Whose conductivity is intermediate between metals and insulators (2) Whose resistance falls almost to zero at very low temperature (3) Which conduct electricity only at super-high temperature (4) Which conduct electricity only, at super-high temperatures
Last Answer : (2) Whose resistance falls almost to zero at very low temperature Explanation: Superconductivity is a phenomenon of exactly zero electrical resistance and expulsion of magnetic fields occurring in ... lines from the interior of the superconductor as it transitions into the superconducting state.
Description : Super conductors are substances that – (1) offer minimum resistance to flow of electric current (2) conduct electricity at low temperature (3) conduct electricity at high temperature (4) offer high resistance to the flow of electric current
Last Answer : (1) offer minimum resistance to flow of electric current Explanation: A superconductor is a material that can conduct electricity or transport electrons from one atom to another with no ... is released from the material when it reaches the temperature at which it becomes superconductive.
Description : Super conductors are substances that (1) offer minimum resistance to flow of electric current (2) conduct electricity at low temperature (3) conduct electricity at high temperature (4) offer high resistance to the flow of electric current
Last Answer : offer minimum resistance to flow of electric current
Description : Silicon is a _____. A. Superconductor B. Conductor C. Semi-conductor D. Insulator
Last Answer : ANSWER: C
Description : What is the order of energy gap in a conductor, semi conductor, and insulator?.
Last Answer : Conductor - no energy gap Semi Conductor - It is of the order of 1 ev. Insulator - 6 ev (or) more than 6 ev.
Description : Materials having resistivity ranging from 1 to 100 ohm. cm is termed as (A) Conductor (B) Insulator (C) Semi-conductor (D) None of these
Last Answer : (C) Semi-conductor
Description : Due to self-inductance, the coil wires are known as: a. Insulator b. Conductor c. Inductor d. Semi-conductor
Last Answer : c. Inductor
Description : Superconductors are those elements (1) Whose conductivity is intermediate between metals and insulators (2) Whose resistance falls almost to zero at very low temperatures (3) which turn into insulators at very low temperatures (4) which conduct electricity only at super-high temperatures
Last Answer : Whose resistance falls almost to zero at very low temperatures
Description : Is there any metallic substance that does not conduct electricity ?
Last Answer : Characteristics of metallic materials are: jingle when hit, can be beaten into thin sheets , conductor of electricity. Therefore there is no metal that does not conduct electricity. Because if electricity is not transmitted it will not be considered as metal
Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because - (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals
Last Answer : (3) metals are good conductors of heat Explanation: On a chilly day, the room temperature is lower than our body temperature. Since metals have a higher coefficient of thermal conductivity than plastic, they ... from our fingers will flow to the metal cap much more quickly than to the plastic body.
Description : On a cold day when the room temperature is 15°C, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15°C, because : (1) metals ... metals (3) metals are good conductors of heat (4) plastics have a higher thermal conductivity than metals
Last Answer : metals are good conductors of heat
Description : Super conductors are those substances, which (A) Offer no resistance to current flow (B) Conduct electricity at low temperature (C) Offer high resistance to current flow (D) Conduct electricity at high temperature
Last Answer : (A) Offer no resistance to current flow
Description : Graphite is a good (A) Thermal & electrical insulator (B) Conductor of heat (C) Conductor of electricity (D) Both (B) & (C)
Last Answer : (D) Both (B) & (C)
Description : If electrical conductivity increases with the increase of temperature of a substance, then it is a: (1) Conductor (2) Semiconductor (3) Insulator (4) Carborator
Last Answer : (2) Semiconductor Explanation: A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects
Description : If electrical conductivity increases with the increase of temperature of a substance, then it is a (1) Conductor (2) Semiconductor (3) Insulator (4) Carborator
Last Answer : (2) Semiconductor Explanation: A solid substance that has conductivity between that of an insulator and that of most metals, either due to the addition of an impurity or because of temperature effects.
Description : Copper wires are generally used for electrical power transmission instead of iron wire because (1) copper is cheaper than iron (2) copper is lighter than iron (3) copper is a better conductor of electricity than iron (4) copper can take higher power than iron
Last Answer : (3) copper is a better conductor of electricity than iron Explanation: Copper is generally preferred for electrical power transmission instead of iron because of its high electrical conductivity and low resistivity.
Description : Copper wires are generally used for electrical power transmission instead of iron wire because : (1) copper is cheaper than iron (2) copper is lighter than iron (3) copper is a better conductor of electricity than iron (4) copper can take higher power than iron
Last Answer : copper is a better conductor of electricity than iron
Description : A semiconductor is a material with a _____________. A. conductivity higher than a normal conductor B. conductivity higher than a normal insulator C. high conductivity at low temperatures D. low conductivity at high temperatures
Last Answer : Answer: B
Description : With increase in temperature, the thermal conductivity of non-metallic amorphous solids (A) Decreases (B) Increases (C) Remain constant (D) First decreases upto certain temperature and then increases
Last Answer : (B) Increases
Description : In a transistor, the base is _______. (1) an insulator (2) a conductor of low resistance (3) a conductor of high resistance (4) an extrinsic semiconductor
Last Answer : (2) a conductor of low resistance Explanation: A transistor is a semiconductor device used to amplify and switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit.
Description : Ohm's law is valid in case of – (1) semiconductor (2) conductor (3) superconductor (4) insulator
Last Answer : (2) conductor Explanation: Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points. It defines the relationship between the three fundamental, electrical quantities: current, voltage, and resistance.
Description : Electricians use rubber gloves while working because - (1) rubber is an insulator (2) rubber is a good conductor (3) wearing rubber gloves is mandatory (4) rubber makes work easy
Last Answer : (1) rubber is an insulator
Description : Mud houses are cooler in summers and wanner in winters as compared to brick houses because (1) mud is a good conductor (2) mud is a bad conductor (3) mud is a poor insulator (4) evaporation of water causes cooling in summers and sunlight coming through holes causes warming in winters
Last Answer : (2) mud is a bad conductor Explanation: The houses made of mud and thatched roofs are cool in summer and warm in winter as the thatched roof contains large amount of trapped air and also mud is ... . In summer, the outside heat cannot enter the house and in winter, inside heat cannot flow outside.
Description : Ohm’s law is valid in case of (1) semiconductor (2) conductor (3) superconductor (4) insulator
Last Answer : conductor
Description : Mud houses are cooler in summers and warmer in winters as compared to brick houses because (1) mud is a good conductor (2) mud is a bad conductor (3) mud is a poor insulator (4) evaporation of water causes cooling in summers and sunlight coming through holes causes warming in winters
Last Answer : mud is a bad conductor
Description : Certain substances loose their electrical resistance completely at super low temperature. Such, substances are called. (1) Super conductors (2) Semi conductors (3) Dielectrics (4) Perfect conductors
Last Answer : (1) Super conductors Explanation: Superconductors are materials that carry electrical current with little or no resistance when cooled, below a certain temperature. While conventional superconductors need to ... temperature superconductors do so above the boiling point of liquid nitrogen (-196 °C).
Description : Certain substances loose their electrical resistance completely at super low temperature. Such substances are called. (1) Super conductors (2) Semi conductors (3) Dielectrics (4) Perfect conductors
Last Answer : Super conductors
Description : Heating of ferromagnetic materials to a temperature above Curie temperature makes it (A) Insulator for heat & electricity transmission (B) Ferritic (C) Behave like paramagnetic materials (D) Superconductor
Description : A metallic alloy in general as compared to their pure metal components is (A) More corrosion resistant (B) Having higher melting point (C) Having lower hardness, reactivity and fusibility (D) Having lower electrical conductivity
Last Answer : (A) More corrosion resistant
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 : Which class of solids could have London Forces the attractive forces between particles in crystal lattice positions? w) ionic x) covalent y) metallic z) molecular
Last Answer : ANSWER: Z -- MOLECULAR
Description : When electric current passes through a metallic conductor, its temperature rises. This is due to?
Last Answer : When electric current passes through a metallic conductor, its temperature rises. This is due to collisions between conduction electrons and atoms.
Description : Which of the following is a good conductor of heat but bad conductor of electricity? (1) mica (2) asbestos (3) celluloid (4) paraffin wax
Last Answer : (1) mica Explanation: Mica is a good conductor of heat but bad conductor of electricity.
Description : Which of the following is a good conductor of heat but a bad conductor of electricity? (1) Celluloid (2) Rubber (3) Asbestos (4) Mica
Last Answer : (4) Mica Explanation: Good conductors of heat are good conductors of electricity. Mica is an exception which although being a good conductor of heat and a bad conductor of electricity. It is commonly ... to assist in the transfer of the generated heat to the heat sink or chassis for dissipation.
Description : Which of the following is a good conductor of heat but bad conductor of electricity ? (1) mica (2) asbestos (3) celluloid (4) paraffin wax
Last Answer : mica
Description : Which of the following is a good conductor of heat but a bad conductor of electricity ? (1) Celluloid (2) Rubber (3) Asbestos (4) Mica
Last Answer : Mica
Description : Do all solids do not conduct heat at the same rate?
Last Answer : Yes
Description : Diamond is a good thermal conductor. But it is an excellent electrical insulator. How?
Last Answer : Diamond crystal is a three-dimensional network of carbon atoms. All carbon atoms in the network are strongly bonded by carbon-carbon covalent bonds. Therefore diamond crystal has a highly ... in diamond crystal to ficilitate electrial conduction. Thus diamond is an excellent electrical insulator.
Description : Is the surface temperature of white dwarf Stars higher or lower than red super giant?
Last Answer : Yes dwarf has higher temperature
Description : A glass tube of smaller diameter is used while performing an experiment for the capillary rise of water because (A) It is easier to see through the glass tube (B) Glass tube is cheaper than a metallic ... (C) It is not possible to conduct this experiment with any other tube (D) All of the above
Last Answer : Answer: Option A