Question

2. Plot these data as electromagnetic waves on a graph and find the following:

a. Period

b. Frequency

2.1 Time= 15s

Cycles= 5

2.2 Time= 30s

Cycles= 6s

3. The wavelength of an electromagnetic wave is 450nm, and the speed of light (c) is 3x108m/s. Determine the frequency, energy, and numbers of the electron.

Answer 1

Period=Time/Cycles=15/5=3 s

Frequency=Cycles/Time=5/15=1/3

3.$\nu=c/\lambda=3x10^8/(450x10^{-9})=6.67 x10^{14}s^{-1}$

$E=h\nu=6.63 x10^{-34}x6.67x10^{14}=44.22 x10^{-20}J$

Electron number $44.22x10^{-20}/1.6 x10^{-19}=2.8$ electrons.