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Light waves are electromagnetic waves that travel at 3.00 x 10^8 m/s. The eye is most sensitive to light having a wavelength of 5.50 x 10^-7 m.

a. Find the frequency of this light wave.
b. Find its period.

User Ross Edman
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1 Answer

14 votes
14 votes

Answer:

a. Frequency is 5.45 x 10^14 hz

b. The period = 1.8 x 10^-15 sec {or 1.8 femptoseconds]

Step-by-step explanation:

The velocity of an electromagnetic wave is given by the product of the wave's frequency(f) times its wavelength(λ).

V = λ f where,

V is the wave speed,

f is the wave frequency,

λ is the wavelength.

To find frequency, rearrange to:

f = V/ λ

Light travels at 3.00x10^8 m/sec.

λ is 5.50 x 10^-7 m

f = (3.00x10^8 m/sec)/(5.50 x 10^-7 m) meters cancels, secs is on the bottom]

f = (3.00/5.50)*(10^15) [The base 10 exponent on the bottom ius subtracted from the one on top: 98-(-7)) = 15)

f = 0.545 x 10^15 1/s or hz

f = 5.45 x 10^14 hz

b. The period of a wave is the inverse of it's frequesncy. It is the time it takes for 1 wave to pass. Invert the frequency:

Period = 1/f

Period = 1/(0.545 x 10^15 1/s)

Period = 1.8 x 10^-15 sec {or 1.8 femptoseconds]

Light waves are electromagnetic waves that travel at 3.00 x 10^8 m/s. The eye is most-example-1