Question

An electron in hydrogen atom-stays in its second orbit for 10⁻⁸ s How many revolutions will it make around the nucleus in that time?

[Velocity of electron in second orbit = 1.07 × 10⁶ m/s, radius of electron in second orbit = 2.14 × 10⁻¹⁰ m]

Answer 1

We are given:

Time spent in the second orbit = t = 10⁻⁸ s

Velocity of the electron in second orbit = v = 1.07 × 10⁶ m/s

Radius of second orbit = r = 2.14 × 10⁻¹⁰ m

Circumference = 2πr = 2 × 3.1416 × 2.14 × 10⁻¹⁰

= 13.44 × 10⁻¹⁰ m

Time per revolution = `"Circumference"/"Velocity"`

`= (13.44xx10^-10) /(1.07xx10^6)`

= 1.255 × 10⁻¹⁵ seconds

Number of revolutions = `10^-8/(1.255xx10^-15)`

= 7.97 × 10⁶ revolutions