While obtaining the Bohr radius for the ground state of hydrogen, the speed obtained from the quantisation condition v=mrℏ is substituted in the force balance equation. Which of the following relations is then obtained?
a) ε0r2e2=mr3ℏ2
b) 4πε0r2e2=mr3h2
c) 4πε0r2e2=mr3ℏ2
d) 4πε0r2e2=mr34ℏ2