Question

4. If the linear speed of an electron in 4th orbit is 5.475 x 105 m/s, what
is its speed in 18th Bohr orbit ?
(a) 1.51 x 105 m/s
(b) 1.216 x 105 m/s
(c) 10 m/s
(d) 0.75 x 10 m/s​

Answer 1

Answer:

Ans. b). 1.51×106 m/s

Explanation:

HOPEFULLY this helps you

Answer 2

Answer:

Velocity of electron in 18th orbit is 1.216 x 10⁵ m/s (Option B)

Explanation:

• In context to the given  question we have to find the velocity of electron in 18th Bohr orbit

It is given the speed of an electron in 4th orbit is 5.475 x 10⁵ m/s

we know that

Velocity of electron in Bohr model = 2.18 x 10⁶ x Z/n

where, Z = atomic number

            n = no. of orbit

Velocity of an electron in 4th orbit = 5.475 x 10⁵ m/s

5.475 x 10⁵ m/s = 2.18 x 10⁶ x Z/n

we know it is in 4th orbit

5.475 x 10⁵ m/s = 2.18 x 10⁶ x Z/4

Z = (5.475 x 10⁵x4) / 2.18 x 10⁶

Z = 1.0003 x 10⁻¹

Z= 1 ( hydrogen atom)

Similarly for  18th orbit n= 18 and Z =1

Velocity of electron in18th orbit = 2.18 x 10⁶ x Z/n

Velocity of electron in18th orbit = 2.18 x 10⁶ x 1/18

Velocity of electron in18th orbit = (2.18 x 10⁶)/18

Velocity of electron in 18th orbit =0.1214 x 10⁶ = 1.216 x 10⁵ m/s (approx.)

∴ (Option B) is correct.