Ask a Teacher

write and explain the terms in equation E=mc square?

Einstein's Mass-Energy Relation

Einstein said that mass and energy are equivalent, and are related by the equation :
             E = mc²
where E is the amount of energy produced if mass ma is destroyed, and c is the speed of light (in vaccum).
     Since the speed of light is very, very large, so an extremely large amount of energy is produced even if a small mass gets destroyed. The destruction of mass happens in nuclear reactions (like nuclear fission and fusion) with the liberation of tremendous amount of energy. Please note that in the mass-energy equation, if we put the mass in kilograms (kg), and the speed of light in metres per second (m/s), then the energy will come in joules (J). For example, if a mass of 1 kg of any matter could be destroyed in a nuclear reaction, then the amount of energy produced would be given by Einstein's equation as :
             E = mc²
             E = 1 x (3 x 10⁸)²
             E = 9 x 10¹⁶ J
Thus, 1 kg mas produces a huge amount of energy of 9 x 10¹⁶ joules.