Question

How many wave length of Kr${}^{86}$ are there in 1 metre?

• A. 1553164.13
• B. 1650763.73
• C. 2348123.73
• D. 652169.13

Answer 1

The correct option is B 1650763.73

$K{r}^{86}$ corresponds to orange in the visible region

Hence the wave of $K{r}^{86}$ has a wavelength of about 605 nm.

So, number of wavelengths in $1$ metre $=\frac{1}{605\times {10}^9}=1650763.73$