SIR I have a plant in my house...but on the upper side of the leaf its red but in lower side its green..so how will trap sunlight for photosynthesis?

Dear student,
Please find below the answer:

The leaves which are of different colour like red, brown, purple etc. still have chlorophyll to carry out photosynthesis. It is just that the other pigments like anthocyanin, xanthophylls, etc. mask the green pigment of leaves. 
Also, it is not only chlorophyll that can carry out photosynthesis. Other pigments that bring about the process are- xanthophylls, carotene, phaeophytin etc. 

Hope this clears your doubt.
Regards.