Question

Question 7a: ​ On Earth in 2017, the amount of electrical energy used was 8.03 x 10​16​ J. How much mass would need to be converted directly to energy to release this much energy?







Question 7b: ​ Imagine this conversion of mass to energy all came from nuclear fission reactions of the element uranium. Assume the reaction is 35% efficient: that means that the mass you calculated above to produce the electrical energy is only 35% of the total mass that was converted to energy. The other 65% was “waste” energy. How much total mass was converted to all kinds of energy?









Question 7c: ​The amount of mass actually converted to energy is just a small fraction of the original uranium’s mass: just 0.0000885 of the original mass (0.00885%). Given all these assumptions, how much total mass of uranium must be available to create all the electrical energy used in the world, in one year? (The total reserve of uranium-235 currently available is about 37,000 tonnes, or 3.7 x 10​7​ kg.)

Answer 1

279) on earth in 2017, the amount of elaturica Energy cesed was E = 8:03x10 2. m-mass required to be converted dicechy to energy to release this much energy. 2. By the einstein Energy mass equation. : E = mc². ma E = 8:03x10. 13x103) ² m = 8:03 x. m = 0.892 kg) 276 Now m=0.8 92 kg is only 35% of total mass. and 65% of total mass is waste. energy

.. Let a= total mass of the all kind 35% y = 0.892. 35. x2 =.0.892 100 2= 0.89 2 x 100. 35. * 1 2 = 2.5492 kg. and answer. This is the total mass. any total available mass of uranium.is. mu 37x10 kg. :. The total mass of uranium available. to create all the eletrical energy used in the world in one year is. mi=0.00885% of mu. mi= 0.00885 x 3:1X10? * mi= 3274 5kg.) and answers. 100