
import math

# Define the constants
m = 14100 / (6.022 * 10**23)  # in g
V_bar = 0.703  # in mL/g
rho = 0.998  # in g/mL
s_bar = 1.91 * 10**-13  # in s
eta = 1.002  # in g/m.s

# Calculate f
f = m * (1 - V_bar * rho) / s_bar  # in g/s

# Calculate r
r = f / (6 * math.pi * eta)  # in m
r_nm = r * 10**9  # convert to nm
print(r_nm)

