Asked by H.T
a 0.5 m^2 solar collector radiation from the sun and focuses it on 250g of water that is inially at 23 degrees . the average intensity of radiation arriving from the sun at this location is 550 Wm^-2. if you assume that this is collected with 100% efficiency. how much time is required for the collector to raise this temperatuer to boiling, at 100 degrees