Question

What distance does electromagnetic radiation travel in 10.2 fs ? Express your answer using three significant figures.

Part A

What is the frequency of radiation that has a wavelength of 11 μm , about the size of a bacterium?

Express your answer using two significant figures.

What is the wavelength of radiation that has a frequency of 5.40×10¹⁴ s−1 ?

Would the radiations in part (a) or part (b) be visible to the human eye?

The radiation in (a) is "visible" to humans. The radiation in (b) is "visible" to humans

.What distance does electromagnetic radiation travel in 50.0 μs ?

Answer 1

1) What distance does electromagnetic radiation travel in 10.2 fs

fs means femito second

time = t = 10.2 fs = 10.2 x 10^-15 s

c = light velocity = 3 x 10^8 m / sec

velocity = distance / time

distance = velocity x time

              = 3 x 10^8 x 10.2 x 10^-15

              = 3.06 x 10^-6 m

distnance = 3.06 x 10^-6 m

2) part A ) What is the frequency of radiation that has a wavelength of 11 μm

wave length = 11 μm = 11 x 10^-6 m

C = 3 x 10^8 m / sec

frequency   = C / wave length

                  = 3 x 10^8 / 11 x 10^-6

                  = 2.7 x 10^14 Hz

3) part B)

frequency = 5.40×10¹⁴ s−1

wave length = 3 x 10^8 / 5.40×10¹⁴

                     = 5.6 x 10^-7 m

                     = 0.56 μm

part a) visible to human eye

4) time = 50.0 μs   = 50 x 10^-6 sec

distance = 3 x 10^8 x 50 x 10^-6

              = 15000 m