Question

an electron in a tv picture tube is accelerated through a potential difference of 10 kv before it hits the screen. what is the kinetic energy of the electron in electron volts? (1 ev = 1.6 × 10 −19 j)

Answer 1

The kinetic energy of the electron in electron volts is 10000 eV

Step-by-step explanation:

Given;

potential difference of the electron = 10 kV = 10,000 V

one electron volt = 1 ev = 1.6 × 10⁻¹⁹ J

To determine the kinetic energy of the electron in electron volts; we multiply the potential difference of the electron by 1.6 × 10⁻¹⁹ J.

`10\ kV = 10000 \ V \\\\E = 10000*1.602*10^(-19) = 1.602*10^(-15) \ J\\\\in \ electron \ volt = (1.602*10^(-15))/(1.602*10^(-19)) = 10000 \ eV`

Therefore, the kinetic energy of the electron in electron volts is 10000 eV

Answer 2

1.6×10⁻¹⁵ J or 10000 ev

Step-by-step explanation:

E = eV............... Equation 1

Where E = Energy of the electron, V = Potential difference, e = charge on an electron.

Given: V = 10 kv = 10×100 v = 10000 v,

Substitute into equation 1

E = 10000 ev

If 1 ev = 1.6×10⁻¹⁹ J,

Then, 10000 ev = 1.6×10⁻¹⁹×10000 = 1.6×10⁻¹⁵ J.

Hence the kinetic energy of the electron = 1.6×10⁻¹⁵ J or 10000 ev