Answer:
a) 22.471 x 10^-11 N
b) -22.471 x 10^-11 N
Explanation:
given the charge on an electron = 1.6 x 10^-19 C
nucleus contain 79 protons
hence, charge on nucleus =79 x 1.6 x 10^-19 C
distance r = 9 x 10^-9 m
a) therefore, force exerted by the gold nucleus on the electron = Kqe/r^2
= 9 x 10^9 x 79 x 1.6 x 10^-19 x 1.6 x 10^-19 / ( 9 x 10^-9 m)^2
= 22.471 x 10^-11 N
b) force exerted by the electron on the gold nucleus ; = -Force exerted by gold on electron ( From newton third law of motion)
= - 22.471 x 10^-11 N