9.) part 1
You will need to know the mass of the proton and electron to solve this problem. Atomic physicists usually ignore the eﬀect
of gravity within an atom. To see why, we may calculate and compare the magnitude of the ratio of the electrical force and gravitational
force Fe/Fg between an electron and a proton separated by a distance of 8 m.
What is the magnitude of the electrical force? The Coulomb constant is 8.98755e9 N · m2/C^2, the gravitational
constant is 6.67259e−11 m3/kg · s^2, the mass of a proton is 1.67262e−27 kg, the mass of an electron is 9.10939e−31 kg,
and the elemental charge is 1.602e−19 C.
Answer in units of N
10.) part 2
What is the magnitude of the gravitational
force?
Answer in units of N
11.) part 3
What is the ratio of the magnitude of the electrical force to the magnitude of the gravitational force?
You will need to know the mass of the proton and electron to solve this problem. Atomic physicists usually ignore the eﬀect
of gravity within an atom. To see why, we may calculate and compare the magnitude of the ratio of the electrical force and gravitational
force Fe/Fg between an electron and a proton separated by a distance of 8 m.
What is the magnitude of the electrical force? The Coulomb constant is 8.98755e9 N · m2/C^2, the gravitational
constant is 6.67259e−11 m3/kg · s^2, the mass of a proton is 1.67262e−27 kg, the mass of an electron is 9.10939e−31 kg,
and the elemental charge is 1.602e−19 C.
Answer in units of N
10.) part 2
What is the magnitude of the gravitational
force?
Answer in units of N
11.) part 3
What is the ratio of the magnitude of the electrical force to the magnitude of the gravitational force?

gravitational force =
Fg = GMm/R^2 FG = 6.67*10^11*1.672*10^27*9.11*10^31/64
Fg = 1.587*10^69 N
electrical force = kQ^2/8^2 = 9*10^9*(1.6*10^19)^2/64
Fe = 3.6*10^30 N
Ratio = 3.6*10^30/1.59*10^69 = 2.26*10^39
OG
Fg = GMm/R^2 FG = 6.67*10^11*1.672*10^27*9.11*10^31/64
Fg = 1.587*10^69 N
electrical force = kQ^2/8^2 = 9*10^9*(1.6*10^19)^2/64
Fe = 3.6*10^30 N
Ratio = 3.6*10^30/1.59*10^69 = 2.26*10^39
OG