Orbits — Set 3
Technology · कक्षाएं · Questions 21–30 of 40
What is the 'GEMS' term for an orbit that has a period of exactly one sidereal day?
Correct Answer: A. Geosynchronous Orbit
A Geosynchronous orbit matches the rotation of the Earth. If it is also circular and equatorial, it is called Geostationary. This synchronization ensures the satellite stays at a consistent longitude.
The 'GEMS' fact about LEO (Low Earth Orbit) is that its altitude is generally below?
Correct Answer: C. 2,000 km
LEO is the region between the Earth's atmosphere and the inner radiation belts. Most man-made objects in space, including the ISS, reside in this zone. It is preferred for missions requiring high-resolution imagery.
Which 'GEMS' concept explains why a satellite doesn't fall straight down to Earth?
Correct Answer: D. Centrifugal force balancing gravity
A satellite is essentially in a state of 'perpetual fall' where its forward speed is fast enough to match the curve of the Earth. The inward pull of gravity is balanced by the outward tendency of inertia. This balance keeps it in a stable path.
In which 'GEMS' orbit do the majority of remote sensing satellites operate?
Correct Answer: D. Sun-Synchronous Polar Orbit
Sun-Synchronous orbits provide consistent shadows for analyzing ground features. This allows scientists to compare images of the same location taken over different days. These satellites typically circle the Earth from pole to pole.
What 'GEMS' name is given to the orbit used by Russia to cover its northern territories?
Correct Answer: A. Molniya
The Molniya orbit is a highly elliptical orbit with an inclination of 63.4 degrees. It allows satellites to remain visible for long periods in high-latitude regions. This was a clever engineering solution to the limitations of geostationary orbits.
Which 'GEMS' location is ideal for placing a solar-observing satellite like Aditya-L1?
Correct Answer: D. Lagrange Point L1
The L1 point between the Earth and the Sun provides an uninterrupted view of the Sun. It is a point of gravitational stability where the satellite can stay with minimal fuel. India's Aditya-L1 mission specifically targets this point.
What 'GEMS' term describes the process of an orbit shrinking due to air resistance?
Correct Answer: D. Orbital Decay
Orbital decay is the gradual decrease in the distance between two orbiting bodies. For satellites in LEO, this is caused by friction with the upper atmosphere. Eventually, the satellite burns up or crashes upon reentry.
How many 'GEMS' primary categories of Earth orbits are defined by altitude?
Correct Answer: D. Three
Earth orbits are generally categorized as Low Earth Orbit (LEO), Medium Earth Orbit (MEO), and High Earth Orbit (HEO). GEO is the most significant type of HEO. Each category serves different technological and scientific purposes.
What is the 'GEMS' name for the angle between the orbital plane and the equatorial plane?
Correct Answer: B. Inclination
Inclination determines how much of the Earth's surface the satellite can 'see'. An inclination of 90 degrees is a polar orbit, while 0 degrees is an equatorial orbit. It is a fundamental parameter in orbital mechanics.
Which 'GEMS' orbit altitude is approximately 20,000 km, used by navigation satellites?
Correct Answer: B. Medium Earth Orbit
MEO is used for GPS because it offers a balance between coverage area and signal strength. At this height, a satellite can be seen by a large portion of the Earth simultaneously. It is less crowded than LEO.