Question

(a) Calculate the range of wavelengths (in m) for X-rays given their frequency range is 30,000 to 3.0 ? 107 THz. smaller value 1e-8 Incorrect: Your answer is incorrect. m larger value m (b) Do the same for the FM frequency range of 88.0 to 108 MHz. smaller value 3.4 Incorrect: Your answer is incorrect. m larger value m

Answer 1

X-rays are electromagnetic waves so, c (speed of light)= 3e8 m/s

We know, speed of light = wavelength*frequency  ( in 1 THz, we have 10¹² Hz)

wavelength = speed of light / frequency

wavelength = 3e8 / 3e16

wavelength = 1e-8 m or 10 nm ( maximum value)

Similarly, wavelength = 3e8 / 3e19 ( in 1 THz, we have 10¹² Hz)

wavelength = 1e-11 m or 0.01 nm (Minimum value)

Similarly, For FM waves (Remember these are sound waves, so we need to take speed of sound which is 343 m/s at sea level)

wavelength = 343 / 8.8e7

wavelength = 3.89e-6 m (maximum)  

Also, wavelength = 343 / 108e6 = 3.175e-6 m (minimum)