COMEDK · Physics · 29. Nuclear Physics
When the speed of light becomes \(\dfrac{2}{3}\) of its present value, the energy released in a given atomic explosion would:
- A decrease by \(\dfrac{2}{3}\) of its initial value
- B decrease by \(\dfrac{4}{9}\) of its initial value
- C decrease by \(\dfrac{5}{9}\) of its initial value
- D decrease by \(\dfrac{\sqrt{5}}{9}\) of its initial value
Answer & Solution
Correct Answer
(C) decrease by \(\dfrac{5}{9}\) of its initial value
Step-by-step Solution
Detailed explanation
Initial energy: \(E_i = \Delta mc^2\) New speed of light: \(c' = \dfrac{2}{3}c\) New energy: \(E_f = \Delta m \left(\dfrac{2}{3}c\right)^2 = \dfrac{4}{9}\Delta mc^2 = \dfrac{4}{9}E_i\) Decrease \(= E_i - E_f = E_i - \dfrac{4}{9}E_i = \dfrac{5}{9}E_i\) The energy decreases by…
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