Project Seafarer was an ambitious program to construct an enormous antenna, buried underground on a site about 10000 km^2 in area. Its purpose was to transmit signals to submarines while they were deeply submerged. Ordinarily, electromagnetic radiations do not penetrate very far into conductors such as seawater. Assume that the effective wavelength was 3.5 x 10^4 Earth radii.

(a) What would be the frequency of the radiations emitted? (units in Hz)

(b) What would be the period of the radiations emitted? (Units in seconds)

Question

Physics

Noelle Mayer

3 March, 10:42

Project Seafarer was an ambitious program to construct an enormous antenna, buried underground on a site about 10000 km^2 in area. Its purpose was to transmit signals to submarines while they were deeply submerged. Ordinarily, electromagnetic radiations do not penetrate very far into conductors such as seawater. Assume that the effective wavelength was 3.5 x 10^4 Earth radii.

(a) What would be the frequency of the radiations emitted? (units in Hz)

(b) What would be the period of the radiations emitted? (Units in seconds)

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Answers (1)

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Ranger · Answer 1

a) 1.345*10^ (-3) Hz

b) T = 743.16 s

Explanation:

Formula for calculating the value of the frequency (f) of the radiationis

f = c / λ ... (1)

Here c = speed of the light = 3.0*10^8m/s

λ = 3.5x10^4 RE

Ordinarily, electromagnetic radiations do not penetrate very farinto conductors such as seawater. Take the Earth's radius to be 6370 km.

= (3.5x 10^4) (6370*10^3m)

a) so, f = [3*10^8] / (3.5x 10^4) (6370*10^3m) = 1.345*10^ (-3) Hz

b) Now time period is T = 1 / f

T = 743.16 s