During a reaction, $170 \mu \mathrm { J }$ of energy is released. What change of mass would accompany this release? $\left( c = 3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } \right)$
A) $1.9 \times 10 ^ { - 21 } \mathrm {~kg}$
B) $1.5 \times 10 ^ { - 13 } \mathrm {~kg}$
C) $5.1 \times 10 ^ { - 4 } \mathrm {~kg}$
D) $4.8 \times 10 ^ { - 18 } \mathrm {~kg}$

Question

Quizplus · Accepted Answer

The correct answer is A because the change in mass is given by the equation $E=mc^2$, where $E$ is the energy released, $m$ is the change in mass, and $c$ is the speed of light. Substituting the given values into the equation, we get:$$170 \mu \mathrm { J } = m (3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } )^2$$$$m = \frac {170 \mu \mathrm { J } } {(3.0 \times 10 ^ { 8 } \mathrm {~m} / \mathrm { s } )^2} = 1.9 \times 10 ^ { - 21 } \mathrm {~kg}$$

During a Reaction 170μJ170 \mu \mathrm { J }170μJ Of Energy Is Released

During a Reaction $170 \mu \mathrm { J }$ Of Energy Is Released