Respuesta :

Answer:

The speed of electron is [tex]8.7\times10^{6}\ m/s[/tex]

Explanation:

Given that,

Separation of the plate = 1.20 cm

Suppose the field is [tex]E=1.80\times10^{4}\ N/C[/tex].

If the electron is accelerated from rest near the negative plate and passes through a tiny hole in the positive plate.

What the speed does it leave the hole?

We need to calculate the acceleration

Using formula of electric force

[tex]F = qE[/tex]

[tex]ma=qE[/tex]

[tex]a=\dfrac{qE}{m}[/tex]

We need to calculate the speed of electron

Using equation of motion

[tex]v^2=u^2+2as[/tex]

[tex]v^2=2as[/tex]

Put the value of acceleration in the formula

[tex]v^2=2\times\dfrac{qE}{m}\times s[/tex]

Put the value into the formula

[tex]v^2=2\times\dfrac{1.6\times10^{-19}\times1.80\times10^{4}\times1.20\times10^{-2}}{9.11\times10^{-31}}[/tex]

[tex]v=\sqrt{2\times\dfrac{1.6\times10^{-19}\times1.80\times10^{4}\times1.20\times10^{-2}}{9.11\times10^{-31}}}[/tex]

[tex]v=8.7\times10^{6}\ m/s[/tex]

Hence, The speed of electron is [tex]8.7\times10^{6}\ m/s[/tex]