Question

на поверхность вольфрама падает излучение с длиной волны 220 нм. Определить максимальную скорость вылетающего из него электронов, если поверхнностный скачок потенциала для вольфрама равен 4,56 В

Answer 1

уже сегодня такая задача была, вы их че копируете друг у друга?) ход решения если будет нужен то вопросы в личку, а так сразу конечная формула $v=\sqrt{2*U*q/me-2h*\lambda/c*me$, где с-скорость света, h-постоянная планка, me-масса электрона, q-заряд электрона

Answer 2

Calculation of the Maximum Speed of Electrons Emitted from Tungsten

To determine the maximum speed of electrons emitted from tungsten when radiation with a wavelength of 220 nm falls on its surface, we can use the equation for the maximum kinetic energy of emitted electrons:

E_max = eV

where E_max is the maximum kinetic energy of the emitted electrons, e is the elementary charge (1.6 x 10^-19 C), and V is the surface potential barrier (also known as the work function) of tungsten.

Given that the surface potential barrier for tungsten is 4.56 V, we can substitute this value into the equation to find the maximum kinetic energy:

E_max = (1.6 x 10^-19 C) * (4.56 V)

Calculating this expression gives us:

E_max = 7.296 x 10^-19 J

To find the maximum speed of the emitted electrons, we can use the equation for kinetic energy:

E_max = (1/2)mv^2

where m is the mass of the electron (9.11 x 10^-31 kg) and v is the maximum speed of the emitted electrons.

Rearranging the equation, we can solve for v:

v = sqrt((2 * E_max) / m)

Substituting the values into the equation, we get:

v = sqrt((2 * 7.296 x 10^-19 J) / (9.11 x 10^-31 kg))

Calculating this expression gives us:

v ≈ 1.367 x 10^6 m/s

Therefore, the maximum speed of the electrons emitted from tungsten when radiation with a wavelength of 220 nm falls on its surface is approximately 1.367 x 10^6 m/s.

Please note that the above calculations assume ideal conditions and do not take into account factors such as the work function of the material, the efficiency of the emission process, or any quantum mechanical effects.