Explore topic-wise InterviewSolutions in Current Affairs.

A gas which obeys the following laws or characteristics is called as ideal gas. 

1) The size of the molecule of gas is zero 

2) There is no force of attraction or repulsion amongst the molecules of gas.

A) Both the statements are true.

Because of inertia of direction when mud (or sparks) leave the rotating wheel, they try of follow a tangential linear motion due to the absence of external force on them.

Correct option is B) protons

Correct option is A) electrons

Correct option is A) electrons

It means that force and acceleration at a point in space are related to the same instant without bothering for the history of the motion.

Force of attraction between two (point) masses separated by a distance is called as gravitational force.

F = \(G\frac{m_1m_2}{r^2}\)

where ‘G’ is constant called the universal gravitational constant = 6.67 × 10^-11 Nm²/kg²

Examples:

1. The motion of moon, artificial satellites around the earth and motion of planets around the sun is due to gravitational force of attraction.

2. The concept of weight of a body in the earth’s gravitational field is due to gravitational force exerted by the earth on a body.

It is kilogram force (i.e., kgf)     1 kgf = 9.8 N

Correct option is C) neutrons

Characteristics of gravitational force:

1. It is always attractive. 

2. It is the weakest of the four basic forces in nature. 

3. Its range is infinite. 

4. Structure of the universe is governed by this force.

Correct option is  A) zero

Electromagnetic force:

1. The attractive and repulsive force between electrically charged particles is called electromagnetic force. 

2. It can be attractive or repulsive. 

3. It is stronger than the gravitational force. 

4. Example: force of friction, normal reaction, tension in strings, collision forces, elastic forces, fluid friction etc. are electromagnetic in nature. 

5. Reaction forces are a result of the action of electromagnetic forces. 

6. Since majority of forces are electromagnetic in nature, our life is practically governed by these forces.

A) Convex lens

A) convex lens

Correct option is  D) all

1. Before agriculture, people obtained food by hunting and gathering. 

2. But this food could not be stored for a long time. 

3. Therefore, all men and women in the community were continuously engaged in acquiring food.

Archaeological evidence is available to show that agriculture first began about 11,000 years ago in Israel and Iraq.

1. work 

2. women 

3. surplus 

4. craftsmen 

5. foodgrains

Buying and selling articles by exchanging goods for goods is called barter system.

Dogs were used to help in hunting.

Houses at the beginning of the New Stone Age were made of wattle and daub?

• Cow : Cow is a very useful animal. It is domesticated for its milk. Cow-dung was used to smear mud walls and in courtyards. Cow-dung is used to make dung cakes for fuel and also is a very good natural manure for agriculture.
• Goats and Sheep : Sheep is useful for its wool and milk. They are also domesticated for their meat.
• Dog : A very useful and faithful animal. It guards household or village-settlements.
• Horse : A very useful, strong and a swift animal. Its strength is used to draw carriages or to transport heavy
• goods. It is also used in travelling. 
• Bullocks : Bullocks are strong and obedient animals. Therefore, they are used to draw carts. They are also used to transport people and heavy objects from one place to another

The goat and sheep were domesticated after the dog

Homo sapiens of the Middle Stone Age domesticated the dog.

1. The dog is used by modern police. 

2. It is used in the investigation of crimes as a dog can sniff the body odour and bloodstains on the clothes. 

3. It leads police to the person who has committed heinous crimes like murder.

The dog is the first animal to have been domesticated.

1. Capture the wild animal. 

2. Taming the wild animal by giving them the training to live with humans. 

3. Obtaining useful materials like milk from these animals and training them to work as beasts of burden for the humans.

1. domesticated 

2. animal husbandry 

3. dog 

4. goat, sheep 

5. hunting

1. salt 

2. salt 

3. salt 

4. chiefs 

5. protection

The village community laid rules for mutual cooperation in order to keep this system of trade and distribution of resources running smoothly.

The chiefs were also entrusted with the task of protection of the village.

Salt traders traded articles they received in exchange of salt.

Essential things like sharing of agricultural tasks and water resources and the security of the villagesettlements gained importance.

Salt was an essential item in the village settlement.

The population of village-settlements grew because food was available in plenty.

They built protective walls and moats around the village-settlements to protect them selues from floods, wild animals and outsiders who stole the village cattle.

People responsible for the implementation of these rules became the chiefs of villagesettlements.

. grew 

2. village-settlements 

3. quadrangular 

4. clan 

5. extended 

6. house, courtyard 

7. agricultural

Regional differences are seen in the styles of constructing houses, depending on the local climate.

In order to dig deeper into the soil to sow the seeds, the stick was weighted in the centre using a perforated stone.

The New Stone Age women made earthen pots and other earthen objects by hand.

1. It appears from the plans of the houses and the village-settlements that people staying there belonged to a single class. 

2. It means that they were all related to one another. 

3. Thus, the entire village-settlement was an extended family

i. The population of the village-settlements grew because food was available in plenty after agriculture 

ii. They also built bigger houses to accommodate their expanding population.

Protective walls and moats were built around the village-settlements to protect them from floods, wild animals and outsiders who stole village cattle.

1. uxomen 

2. pointed 

3. agricultural 

4. agricultural 

5. agriculture

1. Women are credited to have started cultivation. 

2. They used pointed sticks to sow seeds. 

3. In order to help dig deeper into the soil, the stick was weighted in the centre using a perforated stone.

Agricultural production increased considerably after the plough driven by animals came into use.