## Filters

Q&A - Ask Doubts and Get Answers
Q

# The work function for caesium atom is 1.9 eV. Calculate (a) the threshold wavelength

2.51 The work function for caesium atom is 1.9 eV. Calculate (a) the threshold wavelength

Views

Given the work function for the Caesium atom is $1.9\ eV$.

i.e., $W_{o} = h\nu_{o} = \frac{hc}{\lambda_{o}}$   Or   $\lambda_{o} = \frac{hc}{W_{o}}$

As $1\ eV = 1.602\times10^{-19}J$

$\therefore 1.9\ eV =1.9\times1.602\times10^{-19}J =3.0438\times10^{-19}J$

$\lambda_{o} = \frac{(6.626\times10^{-34}Js)(3.0\times10^8)J}{3.0438\times10^{-19}J} =6.5306\times 10^{-7} m$

Therefore, the threshold wavelength is 6.53× 10-7 m.

Exams
Articles
Questions