Explanation:
Given that,
(a) Frequency, [tex]f_1=4\times 10^{19}\ Hz[/tex]
All electromagnetic wave moves with the speed of light. It is given by :
[tex]c=f\lambda[/tex]
[tex]\lambda_1=\dfrac{c}{f_1}\\\\\lambda_1=\dfrac{3\times 10^8}{4\times 10^{19}}\\\\\lambda_1=7.5\times 10^{-12}[/tex]
(b) Frequency, [tex]f_2=5.5\times 10^{1=9}\ Hz[/tex]
All electromagnetic wave moves with the speed of light. It is given by :
[tex]c=f\lambda[/tex]
[tex]\lambda_2=\dfrac{c}{f_2}\\\\\lambda_2=\dfrac{3\times 10^8}{5.5\times 10^{9}}\\\\\lambda_2=0.054\ m[/tex]
Hence, this is the required solution.
