Question

The wavelength of light is 4000A then the number of waves in 1 mm is​

Answer 1

2500

Step-by-step explanation:

1 Angstrom (1 A) corresponds to

`1 A = 10^(-10) m`

Therefore we can convert the wavelength of the light from Angstroms to meters:

`\lambda = 4000 A = 4000 \cdot 10^(-10) m = 4\cdot 10^(-7) m`

We also know that

`1 mm = 1\cdot 10^(-3) m`

So the number of waves in 1 mm of distance is:

`n=(1\cdot 10^(-3) m)/(4\cdot 10^(-7) m)=2500`