GATE Questions

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Secondary pollutants include ozone, which is formed when hydrocarbons (HC) and nitrogen oxides (NOx) combine in the presence of sunlight.

Whereas Primary pollutant are those pollutants that are directly emitted from their sources, like CO2, CO, SO2 as these gases are directly emitted form burning of fossil fuels.

Acid rain, which is formed when sulfur dioxide or nitrogen oxides react with water, sulfuric acid etc.

Hence, Acidrain is a secondary air pollutant.

The most important polymer present in the nucleus is DNA- the master molecule. It is a polymer of Nucleotides.

The Declaration of Independence express Legal rights of citizens.

Satellites orbit the earth at a speed of 28,000 kmph.

Satellites that are further away actually travel slower. The International Space Station has a Low Earth Orbit, about 400 kilometers (250 miles) above the earth's surface. Objects orbiting at that altitude travel about 28,000 kilometers per hour (17,500 miles per hour).

The only active volcano in India is situated in Andaman-Nicobar islands.

Given 7 + 7/7 + 7 x 7 - 7

By using BODMAS rule,

7 + 1 + 7 x 7 - 7

= 8 + 49 - 7

= 57 - 7

= 50.

Hence 7 + 7/7 + 7 x 7 - 7 = 50.

A Contact force is a force applied to a body by another body that is in contact with it. Contact force acts on a point of direct contact between the two objects. This force can either be continuous as a continuous force or can be momentary in the form of an impulse. Contact force is governed by Newton’s Laws.

Examples :: Contact force is responsible for most of the interactions we experience in the daily life.

1. Writing your name with a pen, pushing a car up a hill, lifting an object, etc...

2. Kicking a ball, hammering a nail, etc...

are some of the everyday examples where contact forces are at work.

In the first case, the force is continuously applied by the person on the car or pen or an object while in the second case the force is delivered in a short impulse.

Contact forces are often decomposed into orthogonal components

one perpendicular to the surface in contact called the normal force, and

one parallel to the surface in contact, called the friction force.