Bohr model - radius and velocity

2026 Re-NEET 1 question

1. Consider that an electron is revolving in an excited state of Hydrogen atom with velocity $\sqrt{25.6}\times10^5$ ms$^{-1}$. The radius of the orbit is $x\times10^{-9}$ m. The value of x is: [Take the mass of electron to be $9\times10^{-31}$ kg, charge of electron = $-1.6\times10^{-19}$ C and $\frac{1}{4\pi\varepsilon_0}=9\times10^9$ Nm$^2$C$^{-2}$]