Question

Photoelectrons are observed when a metal is illuminated by light with a wavelength less than 383 nm. What is the metal's work function?

Answer 1

Answer:

5.19 x 10^-19 J

Explanation:

threshold wavelength, λo = 383 nm = 383 x 10^-9 m

Work function,

$\phi =\frac{hc}{\lambda _{0}}$

$\phi =\frac{6.63\times10^{-34}\times 3 \times 10^{8}}{383\times 10^{-9}}$

Ф = 5.19 x 10^-19 J

Answer 2

Answer:

Work function of the metal is 3.24 eV.                                    

Explanation:

It is given that,

Wavelength, $\lambda=383\times 10^{-9}\ m$

Let W is the work function of the metal. It is given by using Einstein's photoelectric effect equation. It is given by :

$W=\dfrac{hc}{\lambda}$

$W=\dfrac{6.63\times 10^{-34}\times 3\times 10^8}{383\times 10^{-9}}$

$W=5.193\times 10^{-19}\ J$

Since, $1\ eV=1.6\times 10^{-19}\ J$

So, W = 3.24 eV

So, the work function of the metal is 3.24 eV. Hence, this is the required solution.