Physics Past Questions and Answers

Calculate the energy of the third level of an atom if the ground state energy is - 24.8eV

In photo-emission, the number of photo-electrons ejected per second depends on the

The particle nature of light is demonstrated by the

The energy of a photo having a wavelength of 10<sup style='font-size: smaller;'>-10</sup>m is<br/>(h= 6.63 x 10 <sup style='font-size: smaller;'>-34</sup>Js, c =3.0 x 10 <sup style='font-size: smaller;'>8</sup>ms<sup style='font-size: smaller;'>-1</sup>)

What is the least possible error encountered when taking measurement with a meter rule?