Rest mass energy of an electron is:
Correct answer: A. 0.511 MeV
- A. 0.511 MeV
- B. 1 MeV
- C. 8.0x10 J
- D. None of the above
Explanation
Eo=moc^2Where,c2= velocity of light which is 3×10^8 m/smo=rest mass of an electron which is 9.11×10−31 kgEo=rest mass energyPut value of rest mass of an electron and velocity of light in above equation,We get,Eo=9.11×10−31 × (3×10^8)^2Solve this we get,Eo=8.91×10^−14 JWe can convert joule into eV, as our options are also in eV.We know that, 1J=1.6×10−19 eVEo= (8.91×10^−14) / (1.6×10^−19 eV)Eo =0.511MeV
Last updated
About Quantum Theory and Radiation
Quantum theory treats electromagnetic radiation as packets of energy called photons, with energy proportional to frequency through E equals hf. The topic covers Planck's hypothesis, photon momentum, the photoelectric effect, threshold frequency, work function and wave particle duality, distinguishing quantised energy exchange from classical continuous radiation.
Practise Dawn of Modern Physics
739 free Dawn of Modern Physics MCQs from Physics, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Physics questions like this
Physics is on 13 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
0.001 kg mass will be equivalent to_________________?
A black body emitting all the radiation in the visible region appears________.
A black body has the property to _____________ all the radiation entering it.
A black body is one that
A blacksmith is heating an iron axe on a high degree burner. While heating the axe, he noted that different colours are produced. Which of the following colours shows the highest temperature of the iron axe?