India’s satellite launch vehicles

35. With reference to India’s satellite launch vehicles, consider the following statements:
1. PSLVs launch the satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
2. Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
3. GSLV Mk III is a four-staged launch vehicle with the first and third stages using solid rocket motors; and the second and fourth stages using liquid rocket engines.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 and 3
(c) 1 and 2
(d) 3 only

Ans:(a) 1 only
Explanation:-

• PSLVs launch the satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
• Satellites launched by GSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
• GSLV Mk III is a three-stage heavy lift launch vehicle developed by ISRO. The vehicle has two solid strap-ons, a core liquid booster and a cryogenic upper stage.
• GSLV Mk III is designed to carry 4 ton class of satellites into Geosynchronous Transfer Orbit (GTO) or about 10 tons to Low Earth Orbit (LEO), which is about twice the capability of GSLV Mk II.
• The two strap-on motors of GSLV Mk III are located on either side of its core liquid booster. Designated as ‘S200’, each carries 205 tons of composite solid propellant and their ignition results in vehicle lift -off . S200s function for 140 seconds. During strap-ons functioning phase, the two clustered Vikas liquid Engines of L110 liquid core booster will ignite 114 sec after lift -off to further augment the thrust of the vehicle. These two engines continue to function after the separation of the strap-ons at about 140 seconds after lift -off.
• Statement 2 is wrong because it is GSLV that appears to remain permanently fixed in the same position in the sky.
• Statement  3  is  also  wrong  because GSLV  Mk  III  is  a three-stage  launch  vehicle  with  the first  stage using solid fuel, the second stage liquid fuel and the third stage cryogenic technology with the use of liquid hydrogen and oxygen.