Question

A diathermy machine, used in physiotherapy, generates electromagnetic radiation that gives the effect of "deep heat" when absorbed in tissue. One assigned frequency for diathermy is 915.00 MHz. What is the wavelength of this radiation

Answer 1

The wavelength of this radiation = 0.3279 m

Step-by-step explanation:

For a wave, the speed (v), frequency (f) and the wavelength (λ) are related through the relation

v = fλ

f is given in the question as 915 MHz = (915 × 10⁶) Hz = (9.15 × 10⁸) Hz

v = speed of light = (3.0 × 10⁸) m/s (since electromagnetic waves/radiation travel with the speed of light)

λ = ?

λ = (v/f)

λ = (3.0 × 10⁸)/(9.15 × 10⁸)

λ = 0.3279 m

Answer 2

The wavelength of the given radiation is 0.327 m

Step-by-step explanation:

The wavelength and the frequency of a wave are related by the formula, given below:

v = fλ

where.

v = speed of wave

f = frequency of wave = 915 MHz = 915000000 Hz

λ = wavelength of the wave = ?

For the electromagnetic radiations we know that:

v = c = speed of light = 3 x 10^8 m/s

Therefore,

c = fλ

λ = c/f

λ = (300000000 m/s)/(915000000 Hz)

λ = 0.327 m