Respuesta :
Explanation:
We know that,
Energy = [tex]k \frac{qQ}{r}[/tex] .......... (1)
and, Energy = [tex]\frac{1}{2}mv^{2}[/tex] ............ (2)
Now, equating both equations (1) and (2) as follows.
[tex]\frac{1}{2}mv^{2}[/tex] = [tex]k \frac{qQ}{r}[/tex]
v = [tex]\sqrt{\frac{2kqQ}{r \times m}}[/tex]
= [tex]\sqrt{\frac{2 \times 9 \times 10^{9} \times 1.6 \times 10^{-19} \times 1.8 \times 10^{-15}}{0.017 m \times 9.109 \times 10^{-31}}}[/tex]
= [tex]\sqrt{336.62 \times 10^{6}}[/tex]
= [tex]18.34 \times 10^{3}[/tex] m/s
or, = 18 km/s
Thus, we can conclude that initial speed the electron must have in order to reach an infinite distance from the sphere and have zero kinetic energy when it gets there is 18 km/s.
