--%>
Assignment Help - homework help

Problem on spacecraft

Assuming that ground stations are equally distributed on the Earth, how many ground stations are required to maintain constant contact with a spacecraft at 750 km altitude, and 72 degrees inclination?

E

Expert

Verified

Given:

θ (theta) = 72°, Perpendicular distance of spacecraft=750 km.

We know that, 1° = π/180 radian, Radius of earth=6400 km. 
So, 72°= (72*π)/180 radian,
           = 2*π/5
Since,
θ = Arc/Radius,

Therefore, Arc = θ*Radius,
                      =2*π*750/5,
                      = 300π

Circumference of earth = 2*π*Radius
                                  = 2*π*6400

No. of space station = Circumference of earth/2*Arc
                             = (2*π*6400)/(2*300*π)  
                             = 21 space station (approx.)

   Related Questions in Physics

  • Q : Define Kilogram or SI unit of mass

    Kilogram: kg: The basic SI unit of mass that is the only SI unit still maintained by a physical artifact: a platinum-iridium bar reserved in the International Bureau of Weights and Measures at Sevres, France.

    		•
  • Q : Explain Chronology protection conjecture

    Chronology protection conjecture (S.W. Hawking): The notion that the formation of any closed time like curve will (automatically) involuntarily be destroyed by the quantum fluctuations as soon as it is made. In another words, the quan

    		•
  • Q : What is Arago spot What is  Arago

    What is Arago spot? The bright spot which appears in the shadow of a consistent disc being backlit by monochromatic light originating from a point source. &n

    		•
  • Q : Branches of physics Briefly list out

    Briefly list out the name of all the branches of physics?

    		•
  • Q : Calculate the intensity I along y axis

    As shown in the figure below, a source at S is sending out a spherical wave: E1=(A×D/r) cos(wt-2πr/λ); where r is the distance to source

    		•
  • Q : What nucleons altogether in a nucleus

    Explain what does held the nucleons altogether in a nucleus?

    		•
  • Q : Explain Null experiment Null

    Null experiment: The experiment which, after being performed, yields no outcome. The null experiments are just as significant as non-null experiments; when current theory predicts an observable result (or predicts there must be no observable result),

    		•
  • Q : What is Kerr effect Kerr effect (J.

    Kerr effect (J. Kerr; 1875): The capability of certain substances to refract light waves in a different way whose vibrations are in dissimilar directions whenever the substance is located in an electric field.

    		•
  • Q : What is Dulong-Petit law Dulong-Petit

    Dulong-Petit law (P. Dulong, A.T. Petit; 1819): The molar heat capacity is around equivalent to the three times the ideal gas constant: C = 3 R

    		•
  • Q : Calculate time needed for thermocouple

    A thermocouple of K type is suddenly exposed to air with temperature of 1273K, Initial temperature was 293 K. Calculate the time needed for the thermocouple read the temperature with accuracy of better that 99%. Ignore radiation and conduction. The measuring element has a ball shape of diameter o

    		•