Question

why is the box of a solar cooker painted black from inside (b) in places of hot climate it is advised that the outer walls of houses be painted white why

Answer 1

It is so because Black is a very good radiator of heat and when the sun rays fall on the black surface, they help increasing the rate of cooking
b) If the house is painted with a dark colour, it would be heated at a great speed which will result in high temperatures inside the house causing problems to the residents whereas painting them white will keep the house cool and comfortable

Answer 2

the black colour absorbs heat faster as compare to others so to make it more faster heat it is black inside the solar cooker .
In another thing walls of a house need to be cool so they are painted white.