If the rate of emission of energy from a star is 2.7 × 10³⁶ J/sec, the rate of loss of mass in the star will be:
Correct answer: B. 3 × 10¹⁹ kg/sec
- A. 3 × 10¹⁸ kg/sec
- B. 3 × 10¹⁹ kg/sec
- C. 3 × 10²⁰ kg/sec
- D. 3 × 10²¹ kg/sec
Explanation
Using E = mc², mass loss m = E/c² = (2.7 × 10³⁶)/(9 × 10¹⁶) = 3 × 10¹⁹ kg/sec.
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Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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