ICSE Class 7 Answered

Energy can neither be created nor be destroyed it can only be transformed from one form to another. Sun is the ultimate source of energy and it is responsible for all forms of energy. Plants convert light energy into Chemical energy byt he process of photosyntesis.Heat energy from the sun causes change in weather pattern which is responsible for wind. Water evaporates as a result of heat recieved from the sun and constitutes watercycle which in turn resonsible for generation of hydroelectricity.