In hydrogen, the transition from level 2 to level 1 has a rest wavelength of 121.6 nm.

1). Find the speed for a star in which this line appears at wavelength 120.4 nm.

2). Find the direction for a star in which this line appears at wavelength 120.4 nm.

3). Find the speed for a star in which this line appears at wavelength 121.4 nm.

4). Find the direction for a star in which this line appears at wavelength 121.4 nm

5). Find the speed for a star in which this line appears at wavelength 122.2 nm.

6. Find the direction for a star in which this line appears at wavelength 122.2 nm

7). Find the speed for a star in which this line appears at wavelength 122.9 nm.

8). Find the direction for a star in which this line appears at wavelength 122.9 nm.

according to the Bohr'smodel,

The change in wavelength, Δλ = λ₁ - λ₂ = λ₂ν/c

where λ are the respective wavelengths

ν = speed of the stars/objects = ?

c = speed of light = 3 x 10⁸m/s

1. To find the speed for a star in which this line appears at wavelength 120.4 nm.

i. e λ₁ = 120.4nm and λ₂ = 121.6nm

ν = [ (120.4nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = - 2.71x10⁶m/s

2. To find the speed for a star in which this line appears at wavelength 120.4 nm.

i. e λ₁ = 120.4nm and λ₂ = 121.6nm

ν = [ (120.4nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = - 2.71x10⁶m/s

3. To find the speed for a star in which this line appears at wavelength 121.4 nm.

i. e λ₁ = 121.4nm and λ₂ = 121.6nm

ν = [ (121.4nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = - 4.94x10⁵m/s

4. To find the speed for a star in which this line appears at wavelength 121.4 nm.

i. e λ₁ = 121.4nm and λ₂ = 121.6nm

ν = [ (121.4nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = - 4.94x10⁵m/s

5. To find the speed for a star in which this line appears at wavelength 122.2 nm.

i. e λ₁ = 122.2nm and λ₂ = 121.6nm

ν = [ (122.2nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = 9.872x10⁵m/s

6. To find the speed for a star in which this line appears at wavelength 122.2 nm.

i. e λ₁ = 122.2nm and λ₂ = 121.6nm

ν = [ (122.2nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = 9.872x10⁵m/s

7. To find the speed for a star in which this line appears at wavelength 122.9 nm.

i. e λ₁ = 122.9nm and λ₂ = 121.6nm

ν = [ (122.9nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = 2.08x10⁵m/s

8. To find the speed for a star in which this line appears at wavelength 122.9 nm.

i. e λ₁ = 122.9nm and λ₂ = 121.6nm

ν = [ (122.9nm - 121.6nm) / 121.6nm] x 3 x 10⁸m/s

ν = 2.08x10⁵m/s