Which radiation is not dangerous ?
A.Cosmic radiation
B.X-ray radiation
C.Infrared radiation
D.ultraviolet radiation
Category: Renewable Sources of Energy Mcqs
A severe disadvantage of using a mixture of ethylene glycol and water as the heat-exchange fluid for a flat-plate collector is that
A.it has an extremely low specific heat
B.too much pumping power is required
C.it is toxic
D.it does not freeze at -1?C
Solar radiation flux is often reported in langleys per year. The unit langley is equal to
A.1 cal/cm2
B.1 Btu/ft2
C.1 J/m2
D.1 Btu/in2
The coefficient of performance has the units of
A.work
B.pressure
C.temperature
D.none of the above
At 1400 h (local apparent time) the hour angle is
A.30?
B.?30?
C.210?
D.0?
Dry ice is solid
A.water
B.carbon dioxide
C.sodium chloride
D.carbon monoxide
Which of the following statements about using water as a heat-exchange fluid in flat-plate collectors is not true?
A.It is convenient to obtain and handle
B.It has a large heat capacity
C.A large amount of electric power is required to run the water pump
D.Freeze protection can be obtained by mixing with ethylene glycol
The nonconvective layer of solar ponds is an example of
A.single diffusive system
B.double diffusive system
C.triple diffusive system
D.none of the above
Which of the following is maximum for aniline?
A.Flash point
B.Fire point
C.Ignition point
D.Boiling point
A blockbody absorbs all of the incident radiation. It also
A.reflects radiation with 100% efficiency
B.transmits radiation with 100% efficiency
C.emits radiation with 100% efficiency
D.emmits radiation with 0% efficiency
