Satellites (Natural & Artificial) — Homi Bhabha Class 9 Physics MCQs with Solutions
Free Homi Bhabha Class 9 Physics Satellites (Natural & Artificial) MCQs with step-by-step solutions (10 questions). Part of Observing Space / Astronomy. Practise online on Prepizo — no login needed.
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Questions with solutions
Q1 — Satellites (Natural & Artificial) · medium · theory
A natural satellite of the Earth is the:
A. Moon ✓ Correct
B. International Space Station
C. Sun
D. INSAT
Solution: The Moon is Earth's only natural satellite; the others listed are man-made or stars.
Q2 — Satellites (Natural & Artificial) · hard · theory
A geostationary satellite appears to stay fixed above one point on the Earth because its orbital period is:
A. exactly 12 hours
B. about 24 hours (equal to the Earth's rotation period) ✓ Correct
C. about 1 month
D. about 1 hour
Solution: A geostationary satellite orbits once every ~24 hours over the equator, matching the Earth's spin, so it appears stationary.
Q3 — Satellites (Natural & Artificial) · medium · theory
Artificial satellites are commonly used for:
A. communication, weather forecasting and navigation ✓ Correct
B. purifying drinking water
C. growing crops in space
D. producing electricity for homes
Solution: Man-made satellites serve communication, weather monitoring, remote sensing and GPS navigation.
Q4 — Satellites (Natural & Artificial) · hard · theory
A satellite remains in its orbit around the Earth because:
A. the Sun pushes it
B. the gravitational pull of the Earth provides the required centripetal force ✓ Correct
C. its engines fire continuously
D. there is no gravity in space
Solution: Earth's gravity supplies the centripetal force that keeps the satellite moving in its circular/elliptical orbit.
Q5 — Satellites (Natural & Artificial) · medium · theory
India's first artificial satellite, launched in 1975, was named:
A. Mangalyaan
B. INSAT-1A
C. Chandrayaan
D. Aryabhata ✓ Correct
Solution: Aryabhata was India's first satellite, launched in 1975.
Q6 — Satellites (Natural & Artificial) · medium · theory
Which of the following is an Indian series of satellites used for telecommunication and broadcasting?
A. Voyager
B. INSAT ✓ Correct
C. GPS
D. Hubble
Solution: The INSAT (Indian National Satellite) series handles communication and weather services.
Q7 — Satellites (Natural & Artificial) · easy · theory
Which of the following is a NATURAL satellite?
A. The International Space Station
B. The Moon ✓ Correct
C. A GPS navigation satellite
D. A weather-monitoring satellite
Solution: The Moon orbits Earth without being built or launched by humans, making it a natural satellite. The others are artificial satellites placed in orbit by people.
Q8 — Satellites (Natural & Artificial) · easy · theory
A geostationary satellite seems to hover permanently above one fixed spot on Earth because:
A. It actually orbits the Moon, not Earth
B. Its orbital period equals Earth s rotation period of about 24 hours and it orbits above the equator ✓ Correct
C. It does not move at all in space
D. It is held up by a long steel cable to the ground
Solution: A geostationary satellite circles Earth once per day in the same direction as Earth s spin, and directly over the equator. Since it keeps pace with the ground below, it appears fixed in the sky.
Q9 — Satellites (Natural & Artificial) · medium · numerical
For a circular orbit the speed of a satellite is proportional to 1 divided by the square root of its orbital radius. Satellite Q orbits at 4 times the radius of satellite P. Compared with P, satellite Q moves:
A. four times as fast
B. twice as fast
C. one quarter as fast
D. half as fast ✓ Correct
Solution: Speed varies as 1 over √r. With radius multiplied by 4, the speed is multiplied by 1 over √4 = 1/2, so Q moves at half the speed of P.
Q10 — Satellites (Natural & Artificial) · hard · theory
An astronaut floating inside an orbiting space station feels weightless. The best explanation is that:
A. All the air has been removed from the station
B. There is no gravity at all at that altitude
C. The station and astronaut are both continuously falling around Earth at the same rate, so there is no support force between them ✓ Correct
D. The station spins so fast that gravity is cancelled
Solution: Gravity is still strong in orbit; it is what curves the path. Because the station and astronaut fall together at the same rate, the astronaut is not pressed against any surface and so feels weightless (free fall).