Question

What are propellants? What type of propellant is used in SLV-$3$ and ASLV rockets?

Answer 1

A propellant is a chemical substance that is used in the production of energy. It is a material used to move an object by applying a motive force. Due to lightweight and more efficiency compared to the amount used propellants are used in $SLV - 3$ and ASLV .

Complete step by step answer:
We know that propellant is a kind of fuel that is burned with an oxidizer to produce large volumes of very hot gas. It is used as an explosive for propelling projectiles. Common propellants are energetic materials and they consist of fuel like gasoline, jet fuel, rocket fuel, and oxidizer.
The desirable characteristics of a solid propellant are high specific impulse, predictable burning rate. Propellants are used in different space vehicles. The space shuttle uses liquid hydrogen along with a solid booster during the initial stages.
The SLV or satellite launch vehicle is a four-stage rocket with solid propellant motors. A composite solid propellant is used in $SLV - 3$ . It weighs seventeen tonnes with a height of twenty-two meters.
ASLV or augmented satellite launch vehicle is a five-stage solid-fuel rocket developed by the Indian Space research organization. It is a low-cost intermediate vehicle used to demonstrate and validate critical technologies like strap on technology, vertical integration, strap on technology that would be needed for the launch of future vehicles. It also uses composite solid propellant.
Hence, a composite solid propellant is used in both $SLV - 3$ and ASLV.

Note:
Composite propellants are made from solid oxidizers such as ammonium perchlorate or ammonium nitrate. Also generally a liquified gas is used as a propellant and solid propellants are also there. Propellants are burned to decompose to form propellant gas.