When you irradiate a metal with light of wavelength 433 nm in an investigation of the photoelectric effect, you discover that a potential difference of 1.43 V is needed to reduce the current to zero. What is the energy of a photon of this light in electron volts? energy of a photon: Find the work function of the irradiated metal in electron volts. work function:

Respuesta :

Answer:

The right solution is:

(a) 2.87 eV

(b) 1.4375 eV

Explanation:

Given:

Wavelength,

= 433 nm

Potential difference,

= 1.43 V

Now,

(a)

The energy of photon will be:

E = [tex]\frac{6.626\times 10^{-34}\times 3\times 10^8}{433\times 10^{-9}}[/tex]

  = [tex]4.59\times 10^{-19} \ J[/tex]

or,

  = [tex]\frac{4.59\times 10^{-19}}{1.6\times 10^{-19}}[/tex]

  = [tex]2.87 \ eV[/tex]

(b)

As we know,

⇒ [tex]Vq=\frac{hc}{\lambda}-\Phi_0[/tex]

By substituting the values, we get

⇒ [tex]1.43\times 1.6\times 10^{19}=\frac{6.626\times 10^{-34}\times 3\times 10^8}{433\times 10^{-9}}-\Phi_0[/tex]

⇒                       [tex]\Phi_0=2.3\times 10^{-19} \ J[/tex]

or,

⇒                            [tex]=\frac{2.3\times 10^{-19}}{1.6\times 10^{-19}}[/tex]

⇒                            [tex]=1.4375 \ eV[/tex]