Spontaneous combustion is caused by ______．A.An outside heat source heating a substance until it ignitesB.Conduction of heat through a wall of material to the substanceC.Chemical action within a substanceD.All of the above
Spontaneous combustion is caused by ______．
A.An outside heat source heating a substance until it ignites
B.Conduction of heat through a wall of material to the substance
C.Chemical action within a substance
D.All of the above
相关考题：
Which of the following statements represents the function of the compression rings installed at the top of a diesel Engine piston?A.Control the amount of lube oil burned in the combustion chamberB.Transmit heat from the piston to the cylinder linerC.Prevent damage to ring groove inserts by acting as a heat damD.Dissipate combustion chamber gas pressure by channeling it through the ring gap
The three basic components of a fire are chain reaction, heat, fuel, and ____.A.carbon monoxideB.oxygenC.carbon dioxideD.any gaseous substance
Fires resulting from spontaneous(自发的) combustion are usually caused by the improper disposal of______.A.cigarette butts(烟头)B.oily ragsC.burner torchesD.lighted matches
The sum of the sensible heat and the latent heat of any substance is known as ______.A.total heatB.residual heatC.specific heatD.superheat
Spontaneous ignition can result from ______.A.an unprotected drop-light bulbB.careless disposal or storage of materialC.smoking in bedD.worn electrical wires on power tools
______ is the most liable to spontaneous combustion．A.CementB.ChinawareC.Fish mealD.Steel products
Which substance might be subject to spontaneous combustion ________．A.CoalB.Scrap rubberC.LeatherD.All of the above
The lowest temperature required to cause self-sustained combustion of a substance independent of any outside source of ignition is called ______．A.Explosive rangeB.Flash pointC.Ignition temperatureD.Combustion temperature
What quality of a diesel fuel is most significant for efficient combustion ________．A.VolatilityB.ViscosityC.Flash pointD.Specific heat
单选题Spontaneous combustion could occur in（）Apaint thinner in an open canBfuel accumulation in the bilgeCoily rags in an unvented compartmentDgasoline stored in steel drums
单选题Fires resulting from spontaneous combustion are usually caused by the improper disposal of（）.Acigarette buttsBoily ragsCburner torchesDlighted matches
单选题The Earth’s irregular heating is caused by （）.Athe time of dayBthe seasonsCgeographyDAll of the above
单选题The most likely place for a fire to start through the process of spontaneous combustion is in （）.Aan electrical switchboardBthe pressure tanksCthe fuel oil tanksDthe oily rag bin
单选题The sum of the sensible heat and the latent heat of any substance is known as （）.Atotal heatBresidual heatCspecific heatDsuperheat
单选题Incomplete combustion in a running diesel engine can cause piston rings to become stuck as a result of （）Aresidual carbon depositsBlube oil viscosity breakdownCuneven heat expansion of the ringsDuneven heat expansion of the piston
单选题Which of the following statements represents the function of the compression rings installed at the top of a diesel Engine piston?（）AControl the amount of lube oil burned in the combustion chamberBTransmit heat from the piston to the cylinder linerCPrevent damage to ring groove inserts by acting as a heat damDDissipate combustion chamber gas pressure by channeling it through the ring gap
单选题Which of the following modes of heat transfer does NOT require any physical contact between a warmer and a cooler substance?（）ARadiationBConductionCNatural convectionDAll of the above
单选题The four basic components of a fire are chain reaction, heat, fuel, and （）.Acarbon monoxideBoxygenCcarbon dioxideDany gaseous substance
单选题Which of the following statements is correct concerning heat transfer?（）AHeat is given off from a high temperature region known as a heat sinkBHeat transfer rate is affected most by the size of the heat sink involvedCHeat transfer rate is affected most by the temperature difference between the heat source and the heat sinkDHeat transfer by radiation will occur only by mass motion of a fluid substance
单选题For a fire to begin there must be present a combustible material, oxygen or air to （）combustion, and a source of heat at a temperature high enough to start combustion.AbeginBsupportClastDextinguish
单选题The lowest temperature required to cause self-sustained combustion of a substance independent of any outside source of ignition is called （）.Aexplosive rangeBflash pointCignition temperatureDcombustion temperature
单选题Which of the following is true of the heating system of the Johnstown campus?AThe heat is supplied by human bodies only.BThe heat is supplied by both human bodies and other heat-emitting objects.CThe heat is supplied by both human bodies and conventional fuel.DThe heat is supplied by human bodies, other heat-emitting objects, and conventional fuel.
单选题Air circulation is caused or affected by（）.Athe rotation of the earth on its axisBconvection currents caused by differences in radiant heating between equatorial and polar regionsCmountain rangesDAll of the above
单选题The heat required to change a substance from a liquid to a gas without experiencing a temperature change is defined as the latent heat of （）.AfusionBvaporizationCsublimationDcondensation
单选题For cargoes（）grain meals,coal,ventilation is needed to prevent them（）spontaneous combustion.Ai.e./ofBfor instance/awayCfor example/offDsuch as/from
单选题Many cast iron pistons are designed with heat dams, which serve to （）Akeep piston crown temperatures elevated for smoother combustionBreduce the possibility of overheating the top compression ringChelp retain the heat of compression to prevent ignition delayDhelp retain the heat of compression to prevent combustion knock