Physics
Dioptre is the unit of

Focal length of a lens
Power of a lens
Sound intensity
Light intensity

ANSWER DOWNLOAD EXAMIANS APP

Physics
On a cold day when a room temperature is 15oC, the metallic cap of a pen becomes much colder than its plastic body, though both are at the same temperature of 15oC, because

metals are good conductor of heat
plastics have a higher thermal conductivity than metals
metals have higher thermal capacity than plastics
plastics have a lower density than metals

ANSWER DOWNLOAD EXAMIANS APP