If you were capable of converting mass to energy with 100%, efficiency, how much mass would you need to produce 3.5x10^12 Joules of energy?
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Answer:
a) 3.9 x 10⁻⁵ kg
Explanation:
The amount of mass required to produce the energy can be given by Einstein's formula:
[tex]E = mc^2\\\\m = \frac{E}{c^2}[/tex]
where,
m = mass required = ?
E = Energy produced = 3.5 x 10¹² J
c = speed of light = 3 x 10⁸ m/s
Therefore,
[tex]m = \frac{3.5\ x\ 10^{12}\ J}{(3\ x\ 10^8\ m/s)^2} \\\\m = 3.9\ x\ 10^{-5}\ kg[/tex]
Hence, the correct option is:
a) 3.9 x 10⁻⁵ kg