Description : Dynamo is a device for converting – (1) Heat energy into electrical energy (2) Mechanical energy into electrical energy (3) Magnetic energy into electrical energy (4) Chemical energy into electrical energy
Last Answer : (2) Mechanical energy into electrical energy Explanation: A dynamo is a device for converting mechanical energy into electrical energy, esp. one that produces direct current. A dynamo is an ... were based, including the electric motor, the alternating-current alternator, and the rotary converter.
Description : The dynamo is a device for converting (1) Heat energy into electrical energy (2) Mechanical energy into electrical energy (3) Magnetic energy into electrical energy (4) None of these
Last Answer : (2) Mechanical energy into electrical energy
Description : Dynamo is a device for converting (1) Heat energy into electrical energy (2) Mechanical energy into electrical energy (3) Magnetic energy into electrical energy (4) Chemical energy into electrical energy
Last Answer : Mechanical energy into electrical energy
Description : The effect of heat used in converting heat energy to mechanical energy is
Last Answer : change of state of matter.
Description : The device used for converting mechanical energy into electrical energy is called a/an (a) cell (b) transformer (c) dynamo (d) electric motor
Last Answer : Ans:(c)
Description : The nerve fiber is capable of converting which stimuli to electrical energy a. Mechanical b. chemical c. Both d. none of them
Last Answer : Both
Description : In four stroke engine which of the following is also known as power stroke a. Suction stroke b. Compression stroke c. Expansion stroke d. Exhaust stroke (Ans:c) Measurements of fuel and air ... into IC engine,___________its efficiency A. increase B. decrease C. does not alter D. unpredictable on
Last Answer : ANSWER : B
Description : In a heat exchanger, floating head is provided to (A) Facilitate cleaning of the exchanger (B) Increase the heat transfer area (C) Relieve stresses caused by thermal expansion (D) Increase log mean temperature gradient
Last Answer : (C) Relieve stresses caused by thermal expansion
Description : In __________ process, there is an increase in entropy with no degradation of energy. (A) Isothermal expansion (B) Isochoric heat addition (C) Polytropic expansion (D) Isobaric heat addition
Last Answer : (A) Isothermal expansion
Description : The main purpose of providing fins on heat transfer surface is to increase the (A) Temperature gradient (B) Mechanical strength of the equipment (C) Heat transfer area (D) Heat transfer co-efficient
Last Answer : (C) Heat transfer area
Description : Pick out the correct statement. (A) If an insoluble gas is passed through a volatile liquid placed in a perfectly insulated container, the temperature of the liquid will increase (B) A ... compound is defined as the heat of reaction leading to the formation of the compound from its reactants
Last Answer : (D) The heat of formation of a compound is defined as the heat of reaction leading to the formation of the compound from its reactants
Description : Which of the following is the correct statement of the second law of thermodynamics? A. It is impossible to construct an engine working on a cyclic process, whose sole purpose is to convert heat energy ... energy, which can be obtained from a given quantity of heat energy. D. all of the above
Last Answer : Answer: D
Description : 6. Liquefaction of gases cannot be done by (A) Exchange of heat with colder stream (B) Adiabatic expansion through a throttle valve (Joule-Thomson expansion) (C) Merely compressing it beyond critical pressure (D) Adiabatic expansion against a piston or in a turbine
Last Answer : (C) Merely compressing it beyond critical pressure
Description : An adiabatic process is one in which A.no heat enters or leaves the gas B.the temperature of the gas changes C.the change in internal energy is equal to the mechanical workdone D.all of the above
Description : A stress which develops within an object when it attempts to expand or contract in response to a temperature changes, but cannot, due to being held rigidly in place. a. elongation b. thermal stress c. expansion contraction d. thermal expansion
Last Answer : thermal stress
Description : What is a form of mechanical work which is related with the expansion and compression of substances? A. Boundary work B. Thermodynamic work C. Phase work D. System work
Last Answer : Boundary work
Description : Isochoric process is one in which (a) free expansion takes place (b) very little mechanical work is done by the system (c) no mechanical work is done by the system (d) all parameters remain constant
Last Answer : Answer : c
Description : When hot liquid is poured into a thick glass tumbler, it cracks because glass – (1) is a bad conductor of heat so only inner surface expands (2) has high temperature coefficient of expansion (3) has a very low specific heat (4) has low temperature coefficient of expansion
Last Answer : (1) is a bad conductor of heat so only inner surface expands Explanation: When hot liquid is poured into a thick glass tumbler, it cracks because glass is a bad conductor of heat so only inner surface expands.
Description : A solid metallic block weighing 5 kg has an initial temperature of 500°C. 40 kg of water initially at 25°C is contained in a perfectly insulated tank. The metallic block is brought into contact with water. Both of them come to equilibrium. ... .kg-1, K-1is (A) -1.87 (B) 0 (C) 1.26 (D) 3.91
Last Answer : (B) 0
Description : When hot liquid is poured into a thick glass tumbler, it cracks because glass : (1) is a bad conductor of heat so only inner surface expands (2) has high temperature coefficient of expansion (3) has a very low specific heat (4) has low temperature coefficient of expansion
Last Answer : is a bad conductor of heat so only inner surface expands
Description : Pick out the wrong statement. (A) Different solids have different equilibrium moisture curves (B) Total condenser or reboiler is considered equivalent to one theoretical plate in McCabe-Thiele method of ... (D) Even a forced draft cooling tower cannot cool water below the wet bulb temperature
Last Answer : (C) Heat removal load on cooler remains constant, even with increase of the reflux ratio in a distillation column
Description : Pick out the wrong statement. (A) Both annealing and normalising release the internal stresses of the material besides improving the mechanical properties (B) Low carbon steel does not respond to ... are also used for surface hardening (D) Martempering of a material is a hardening process
Last Answer : Option C
Description : Pick out the wrong statement about nucleate boiling. (A) Bubble generation is by expansion of entrapped gas/vapour at small cavities in the surface (B) Surface temperature is greater than the saturation ... less than that in film boiling (D) The temperature is less than that of film boiling
Last Answer : (D) The temperature is less than that of film boiling
Description : Which of the following relations is not applicable in a free expansion process? a. Heat is rejected to zero b. Work done is zero c. Change in temperature is zero d. Heat supplied is zero
Last Answer : Change in temperature is zero
Description : Otto cycle efficiency is higher than Diesel cycle efficiency for the same compression ratio and heat input because in Otto cycle A. combustion is at constant volume B. expansion and compression are isentropic C. maximum temperature is higher D. heat rejection is lower
Description : In order that a cycle be reversible, following must be satisfied (a) free expansion or friction resisted expansion/compression process should not be encountered (b) when heat is being absorbed, temperature of hot ... sub-stance should be same (d) all of the above (e) none of the above.
Last Answer : Answer : d
Description : Which effect of heat is used in conversion of heat energy into mechanical energy?
Last Answer : Change of liquid to gaseous state of matter is most in designing heat engines.
Description : How does mechanical energy change into heat energy?
Last Answer : It can convert in several different ways; one common way isthrough friction.
Description : A steam engine converts the heat energy of steam into _____. (1) Electrical energy (2) Chemical energy (3) Mechanical energy (4) Thermal energy
Last Answer : (3) Mechanical energy Explanation: Steam engine, machine for converting heat energy into mechanical energy using steam as a medium, or working fluid.
Description : Potential flow is characterised by the (A) Irrotational and frictionless flow (B) Irrotational and frictional flow (C) One in which dissipation of mechanical energy into heat occurs (D) Formation of eddies within the stream
Last Answer : (A) Irrotational and frictionless flow
Description : A thermoelectric engine which consists of two dissimilar electric conductors connected at two junctions maintained at different temperatures, converts (a) Electric energy into heat energy [IES-2006] (b ... energy (c) Mechanical work into electric energy (d) Electric energy into mechanical work
Last Answer : (b) Heat energy into electric energy
Description : Thermocouples convert a. heat energy into electrical energy b. heat energy into light energy c. heat energy into mechanical energy d. mechanical energy into heat energy
Last Answer : d. mechanical energy into heat energy
Description : One of the purposes of sub-cooling the liquid refrigerant is to (a) reduce compressor overheating (b) reduce compressor discharge temperature (c) increase cooling effect (d) ensure that only liquid and not the vapour enters the expansion (throttling) valve
Last Answer : Ans: d
Description : The adiabatic throttling process of a perfect gas is one of constant enthalpy (A) In which there is a temperature drop (B) Which is exemplified by a non-steady flow expansion (C) Which can be performed in a pipe with a constriction (D) In which there is an increase in temperature
Last Answer : (C) Which can be performed in a pipe with a constriction
Description : Due to which of the following reasons the cables should not be operated too hot ? (a) The oil may loose its viscosity and it may start drawing off from higher levels (b) Expansion of the ... instability may rise due to the rapid increase of dielectric losses with temperature (e) All of the above
Last Answer : (e) All of the above
Description : A transformer – (1) converts DC to AC (2) is used to decrease or increase AC voltage (3) converts AC voltage to D.C. voltage (4) converts electrical energy into mechanical energy
Last Answer : (2) is used to decrease or increase AC voltage Explanation: Transformers have made longdistance transmission of electric power a practical reality, as AC voltage can be "stepped up" and ... the loads), voltage levels are reduced by transformers for safer operation and less expensive equipment.
Description : A transformer in an electric circuit serves to ____________. A. generate its own electrical power B. transform electrical energy into mechanical energy C. increase or decrease circuit voltage as required D. convert AC current to DC current
Last Answer : Answer: C
Description : A transformer (1) converts DC to AC (2) is used to decrease or increase AC voltage (3) converts AC voltage to D.C. voltage (4) converts electrical energy into mechanical energy
Last Answer : is used to decrease or increase AC voltage
Description : What is a typical process of converting wind energy into electrical energy?
Last Answer : Propellers are turned by the wind, and they turn generators.
Description : In plants, __________ is the process of converting stored energy into energy for plant growth. a. Transpiration b. Photosynthesis c. Respiration d. Pollination
Last Answer : Respiration
Description : The amount of heat energy per kilogram that must be added or removed when a substance changes from one phase to another. a. specific heat b. heat of expansion c. latent heat d. useful heat
Last Answer : latent heat
Description : Pick out the wrong statement pertaining to the cooling towers. (A) In case of induced draft cooling tower, the fan is placed at the top of the tower (B) Effectiveness of ... Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature
Last Answer : (D) Effectiveness of a mechanical draft cooling tower is reduced with increase in air wet-bulb temperature
Description : Heat engine uses ______ energy to produce mechanical work. a. Thermal b. Fluid c. Kinetic d. Electric (Ans:a)
Last Answer : Which of the following is not an internal Combustion (IC) engine? a. Gas engine b. Wankel engine c. Jet engine d. Stirling engine (Ans:d)
Description : Mechanical energy is the combination of kinetic energy and _______. (1) Heat energy (2) Chemical energy (3) Potential energy (4) Nuclear energy
Last Answer : (3) Potential energy Explanation: Mechanical energy is the energy possessed by an object due to either its motion or its stored energy of position. The total amount of mechanical energy is merely the sum of potential energy and kinetic energy.
Description : A photoelectric cell converts – (1) Mechanical energy to electric energy (2) Heat energy to mechanical energy (3) Light energy to chemical energy (4) Light energy to electrical energy
Last Answer : (4) Light energy to electrical energy Explanation: Photoelectric cell or photocell, device whose electrical characteristics (e.g., current, voltage, or resistance) vary when light is incident ... The most common type consists of two electrodes separated by a light-sensitive semiconductor material.
Description : A moving car possesses - (1) sound energy (2) mechanical energy (3) heat energy (4) (d)chemical energy
Last Answer : (2) mechanical energy Explanation: A moving baseball possesses mechanical energy due to both its high speed (kinetic energy) and its vertical position above the ground (gravitational potential energy).
Description : The energy consumed by an AC motor, as strictly reactive power, is _____________. A. used to do mechanical work B. used to establish the magnetic field of the motor C. lost as heat generated by the windings D. lost in doing work to turn the motor itself
Last Answer : Answer: B
Description : The following is the correct order of energy conversion in thermal power plants a. Chemical energy - Mechanical energy - Electrical energy b. Mechanical energy - Chemical energy - Electrical energy c ... - Mechanical energy - Electrical energy d. Heat energy - Electrical energy - Mechanical energy.
Last Answer : a. Chemical energy – Mechanical energy – Electrical energy