physical factors are nothing but the abiotic factors which refers to land,air,water,sunlight etc. we can say that organisms on earth cannot survive without these factors.air which contains oxygen is very precious because oxygen is the breath of our is very necessary because without it life is not possible for us. water is very useful because it indirectly provides us food in the form of fishes etc. so life is not possible without these factors and hence they help for sustenance of the habitat.