The ground state energy of hydrogen atom is –13.6 eV. The kinetic energy (K.E.) and potential energy (P.E.) of the electron in ground state are
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → K.E. = + 13.6 eV, P.E. = – 27.2 eV
In the Bohr model the kinetic energy of the electron is positive, the potential energy is negative, and for the inverse-square Coulomb force they are related to the total energy E in a fixed way.
\( \displaystyle K = -E \qquad U = 2E \)
Putting E = −13.6 eV:
\( K = -(-13.6\,\mathrm{eV}) = +13.6\,\mathrm{eV} \)
\( U = 2 \times (-13.6\,\mathrm{eV}) = -27.2\,\mathrm{eV} \)
Check: \( K + U = 13.6 - 27.2 = -13.6 \) eV, the given ground state energy.
Note: This question is from NCERT (2026-27). NTA sets numerical questions from NCERT too, so do not ignore NCERT while practising numericals.
NCERT (2026-27):
Exercises – …
