Question

An x-ray has a wavelength

Answer 1

Answer:

C

Explanation:

For electromagnetic waves frequency X wavelength = speed of light

                                                f * 2.2 x 10^-11  = 3 x 10^8  m/s

                                         f = 3 x 10^8 / 2.2 x 10^-11

                                            = 1.36 x 10 ^19

                                             = 1.4 x 10^19   with two significant digits