In a dark room with ambient temperature T_(0), a black body is kept at a temperature T. Keeping the temperatre of the black body constant (at T) sunrays are allowed to fall on the black body through a hole in the roof of the dark room. Assuimng that here is no charge in the ambient temperature of room, which of following statement is//are correct (i) The quantity of radiation absorbed by the black body in unit time will increase (ii) Since emissivity = absorptivity, hence, the equantity increase (iii) Black body radiation emitted by black body in unit time in the visible spectrum (iv) The reflected energy in unit time by the black body remains same

In a dark room with ambient temperature T_(0), a black body is kept at

1.	In a dark room with ambient temperature T_(0), a black body is kept at a temperature T. Keeping the temperatre of the black body constant (at T) sunrays are allowed to fall on the black body through a hole in the roof of the dark room. Assuimng that here is no charge in the ambient temperature of room, which of following statement is//are correct (i) The quantity of radiation absorbed by the black body in unit time will increase (ii) Since emissivity = absorptivity, hence, the equantity increase (iii) Black body radiation emitted by black body in unit time in the visible spectrum (iv) The reflected energy in unit time by the black body remains same
Answer» (i).(ii) (ii), (iii) (ii), (iii), (iv) all Solution :(4) SINCE ENERGY is to be absorbed, (i), (ii) O.K. As temperature increase, energy is emitted in FORM of VISIBLE light. (iii) is O.K Reflction DEPENDS on nature of surface and independent of temperature, (iv) is O.K.