Differential amplifiers are used in______________?
(A) Instrumentation amplifiers
(B) Voltage followers
(C) Voltage regulators
(D) Buffers
Heat is transferred simultaneously by condition, convection and radiation_____________?
(A) inside boiler furnaces
(B) during melting of ice
(C) through the surface of the insulted pipe carrying steam
(D) from refrigerator coils to freezer of a refrigerator
For the transmission of heat from one body to another__________?
(A) temperature of the two bodies must be different
(B) both bodies must be solids
(C) both bodies must be in contact
(D) at least one of the bodies must have some source of heating
A perfect black body is one that_____________?
(A) transmits all incident radiations
(B) absorbs all incident radiations
(C) reflects all incident radiations
(D) absorbs, reflects and transmits all incident radiations
When a body reflects entire radiation incident on it, then it is known as____________?
(A) white body
(B) grey body
(C) black body
(D) transparent body
is used for heating non-conducting materials?
(A) Eddy current heating
(B) Arc heating
(C) Induction heating
(D) Dielectric heating
Which of the following heating methods has maximum power factor ?
(A) Arc heating
(B) Dielectric heating
(C) Induction heating
(D) Resistance heating
Which of the following is an advantage of heating by electricity ?
(A) Quicker operation
(B) Higher efficiency
(C) Absence of flue gases
(D) All of the above
method has leading power factor____________?
(A) Resistance heating
(B) Dielectric heating
(C) Arc heating
(D) Induction heating
Which of the following methods of heating is not dependent on the frequency of supply ?
(A) Induction heating
(B) Dielectric heating
(C) Electric resistance heating
(D) All of the above