Question

4. The force between two electrons when placed
in air is equal to 0.5 times the weight of an electron
find the distance between two electrons (mass o
electron= 9.1x10-31kg)
7.2 m 2) 72 cm 3) 72 m 4) 720 m​

Answer 1

Explanation:

here,

weight of electron=0.5×force of electron

mg=0.5×kq1q2/r^2

r^2=0.5kq1q2/mg

given,

m=9.1×10^-31kg

g=9.8m/s^2

q1=q2=1.6×10^-19C

k=9×10^9

so,

r^2=0.5kq1q2/mg

= 0.5×9×10^9×(1.6×10^-19)^2/9.1×10^-31×9.8

=5×9×10^9×2.56×10^-38/9.1×10^-30×9.8

=1.152×10^-27/8.918×10^-29

= 0.129×10^2

=12.91

r^2=12.91

r=√12.91

=3.59m.