πri3⇒rf3=1000ri3 ‌⇒rf=10ri So, released energy ‌=‌ Initial surface energy ‌−‌ final surface ‌ ‌‌ energy ‌ ‌=1000×T×4πri2−T×4πrf2 ‌=4πT(1000ri2−rf2) ‌=4π×0.07(1000ri2−100ri2) ‌=4π×0.07×900ri2 ‌=4π×63×10−6=7.92×10−4J