Question Discussion & Solution

Battery and Engine are part of car but battery and engine are two different entity.

Therefore, above diagram best express relationship between Battery, Engine and Car.

The correct answer is First.

• In the year 2017-18, Rajasthan was the largest millet producing state of India.

Key Points

• Rajasthan was followed by Maharashtra and Karnataka.
• The year 2023 will be observed as the International Year of Millets. 
• The Central Government declared 2018 as the year of millets. 
• Millet Mission comes under the National Food Security Mission (NFSM) which was launched in October 2007. 
• Millets include Jowar and ragi etc.

Additional Information 

• Types of Crops in India:
  • Kharif: Sown in June/July, harvested in September/October, e.g., rice, jowar, bajra, ragi, maize, cotton, and jute.
  • Rabi: Sown in October/December, harvested in April/May, e.g., wheat, barley, peas, rapeseed, mustard grains.
  • Zyad: They are raised between April/June, e.g., melons, watermelons, cucumbers, toor, leafy and other vegetables.

Question: Should examinations be held in the school system?

The argument I says Yes, examinations assess students' academic and non-academic achievements is the correct as evaluation plays important role for checking students performance. 

Argument II No, many students do not like exams is wrong. Student do not like many things that does not mean that is not important. 

Hence, option 1 is the correct answer.

The computer has evolved from a large-sized simple calculating machine to a much smaller machine capable of multiple functionalities. Each generation of computer is designed based on the hardware technology used leading to better, cheaper and powerful computers that are faster and efficient than their predecessors.

Hence, it can be concluded from the table that vacuum tubes were used by the first generation computers.

The correct answer is chemical energy.

Key Points

• The dry cell is a type of electric battery which is used for portable electrical devices.
• Electricity is produced through the dry cells from electrochemical energy. Hence, Option 1 is correct.
• A common dry cell is a zinc-carbon cell.
• The electrolyte is immobilized as a paste by a dry cell, with just enough humidity in it to allow current to flow.
• Like a wet cell, a dry cell can work without spilling in any direction, because there is no free liquid in it.
• The versatility makes it ideal for mobile devices.
• The first wet-cell batteries, in comparison, were usually fragile glass containers featuring lead rods sticking from an open-top.
• Hence, they required careful handling to prevent spillage.
• The dry-cell battery development made a significant advance in battery safety and portability.
• Batteries render electricity from chemical energy.
• Batteries consist of one or more different parts, or cells, which contain an electrolyte called a chemical.
• Every cell has two electrodes that are electrically conductive immersed in its electrolyte.
• The electrodes consist of different materials; one releases electrons into the electrolyte, and the other absorbs them.
• Once an electrical system is attached to the electrodes, an electrical current passes through it and supports its operation with electric power.
• The energy contained in the dry cell is therefore in the form of chemical energy.

Additional Information

• Thermal energy
  • It is also called heat energy 
  • It is produced when a rise in temperature causes atoms and molecules to move faster and collide with each other.
  • The energy that comes from the temperature of the heated substance is called thermal energy.
  • Thermal energy is energy that comes from a substance whose molecules and atoms are vibrating faster due to a temperature rise.
• In physical sciences, mechanical energy
  • It is the sum of potential energy and kinetic energy.
  • It is the macroscopic energy associated with a system.
  • The principle of conservation of mechanical energy states that if an isolated system is subject only to conservative forces, then the mechanical energy is constant.
• Nuclear power
  • It is the use of nuclear reactions to produce electricity.
  • Nuclear power can be obtained from nuclear fission, nuclear decay, and nuclear fusion reactions.
  • Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants.