UV X-rays & Gamma rays are ionizing radiation. UV can damage skin cells, but X-ray and Gamma rays can cause the mutation of genes, which can lead to cancer.
Net energy is the amount of that is actually useable from an energy resource. Net-energy ratio is the ratio of the amount of useable energy from a resource and the amount it takes to make that energy useful. ... An energy source with high energy efficiency provides a lot of work for the amount of energy used.
