KNOW THE DIFFERENCE BETWEEN PSLV AND GSLV !!

You might have heard about PSLV and GSLV rocket launch systems developed by the Indian Space Research Organization, or ISRO, to launch satellites into orbit.In this article we will understand the difference between PSLV and GSLV.

Let us understand this by an example:

Meet my 2 friends Polar and Geo.

I asked both of them to throw a 1.5 kg stone up in the air. Whose stone will go higher?
If everything is right, then normally Geo's stone will go higher than Polar's. Right?
Now if you ask Polar to throw a 0.5 kg stone, he may be able to achieve the same height as Geo's 1.5 kg stone. Whereas, Geo maybe able to throw three or four 1 kg stones to the same height as achieved by Polar's 1 kg stone.

This is the basic difference between GSLV (Geosynchronous Satellite Launch Vehicle) and PSLV (Polar Satellite Launch Vehicle).

Both PSLV (Polar Satellite Launch Vehicle) and GSLV (Geosynchronous Satellite Launch Vehicle) are the satellite-launch vehicles (rockets) developed by ISRO. The PSLV is the older of the two and the GSLV even inherits some of the technologies of the former in its design.

The main reason behind the advent of the GSLV is the capability to lift greater loads into space. While the PSLV can only lift slightly over a ton of payload to GTO (Geostationary Transfer Orbit), the GSLV is capable of lifting more than double that with a rated capacity of 2 to 2.5 tons. One of the main reasons why the GSLV has such an increased load is its utilization of a cryogenic rocket engine for its last stage. The cryogenic rocket engine provides more thrust than conventional liquid rocket engines but the fuel and oxidizer needs to be super cooled in order to keep them in a liquid state.

 

PSLV is a four-staged launch vehicle with first and third stage using solid rocket motors and second and fourth stages using liquid rocket engines. It also uses strap-on motors to augment the thrust provided by the first stage, and depending on the number of these strap-on boosters, the PSLV is classified into its various versions like core-alone version (PSLV-CA), PSLV-G or PSLV-XL variants.

The GSLV is designed mainly to deliver the communication-satellites to the highly elliptical (typically 250 x 36000 Km) Geosynchronous Transfer Orbit (GTO). The satellite in GTO is further raised to its final destination, viz., Geo-synchronous Earth orbit (GEO) of about 36000 Km altitude (and zero deg inclination on equatorial plane) by firing its in-built on-board engines.

 

 

When you look at their track records, it is easy to see that the PSLV is more reliable. With 18 launches, 16 of those were successes while only the first one was a total failure; the remaining one is called a partial failure as the satellite did not reach the intended altitude. The 7 launches of the GSLV have had worse results with 4 ending in failure and only two successes; it also has one partial failure launch.

 

In short:

 

1.The PSLV is older than the GSLV
2.The GSLV has a much greater load capacity than the PSLV
3.The GSLV use cryogenic fuel while the PSLV doesn’t
4.The GSLV has three stages while the PSLV has four stages
5.The GSLV has 4 liquid boosters while the PSLV has 6 solid boosters
6.The PSLV is more reliable than the GSLV

KNOW WHY TRACTORS HAVE VERTICAL EXHAUST !!

Tractors are extremely important agricultural vehicles. These machines are ubiquitous across the globe and range from rather small lawn tractors to giant monster worth hundreds of thousands of dollars. However, most of them have something in common – their exhaust pipes are pointing straight up in front of the driver’s cab. Meanwhile exhaust pipes of cars are located at the back, typically at bottom of the vehicle. Why is that? We will discuss the reason behind the vertical exhaust in this article.

 

Following are the reason why tractors have vertical exhaust :

1) Tractor is a off-road vehicle, usually used in every terrain including water dominated areas, where, there are chances of water to get in exhaust pipe and causing harm to the engine and exhaust system itself.

2) Mounting the exhaust pipe in the front has an added cost advantage – that’s where the engine is and less pipework is required this way. Less pipework – less maintenance as well.

3) Many chemicals are spread on crops or plants by driving tractor on the space between plants. If exhaust system is horizontal and below the driver them harmful and hot emissions can harm the crop.

4.)A normal tractor is constituted of two major parts – it can be split in two, which is occasionally done to repair transmission. Having an exhaust running from front to back would make such repairs hardly possible or very difficult.

Special note - Sometimes the end of exhaust pipe is curved, or has a hinged cover flap which the gas flow blows out of the way, to try to prevent foreign objects (including droppings from a bird perching, rain drops, ice on the exhaust pipe when the vehicle is not being used) getting inside the exhaust pipe.

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