Which of the following statements regarding evacuated tube collectors (ETC) are true?
i) ETC is used for high temperatures upto 150oC
ii) because of use of vacuum between two concentric glass tube, higher amount
of heat is retained in ETC
iii) heat loss due to conduction back to atmosphere from ETC is high
iv) performance of evacuated tube is highly dependent upon the ambient temperature
i & iii b) ii & iii c) i & iv d) i & ii
i) ETC is used for high temperatures upto 150oC
ii) because of use of vacuum between two concentric glass tube, higher amount
of heat is retained in ETC
iii) heat loss due to conduction back to atmosphere from ETC is high
iv) performance of evacuated tube is highly dependent upon the ambient temperature
i & iii b) ii & iii c) i & iv d) i & ii