Question Discussion & Solution

The correct answer is Shifting.

• Jhoom agriculture is also known as Shifting.

Key Points

• Shifting Agriculture:
  • It is practised by the tribals in the forest areas of Assam, Meghalaya, Nagaland, Manipur, Tripura, Mizoram, Arunachal Pradesh, Odisha, Madhya Pradesh, Jharkhand and Andhra Pradesh.
  • In this type of agriculture, a piece of forest land is cleared mainly by tribal people by felling and burning of trees and crops are grown.
• Jhoom is the name of Shifting Agriculture in the north-east region of India.
• Podu, Dabi, Koman or Bringa in Orissa
• Kumari in the Western Ghats.
• Watra in southeast Rajasthan,
• Penda, Bewar or Dahia and Deppa or Kumari in the Bastar district of Madhya Pradesh.

Additional Information

• Names of shifting agriculture around the world:

Concept-

• A cell is defined as the smallest unit of an organism with a nucleus.
• cells are made from the same major classes of organic molecules: nucleic acids, proteins, carbohydrates, and lipids.

• Example- a unit in the tissue of an animal muscle.

Key PointsParts of cell-

Cell membrane

• It is also called the plasma membrane,
• It is found in all cells and separates the interior of the cell from the outside environment.
• It is the outermost wall in the animal cell and placed next to the cell wall in the plant cell.
• Being an outer boundary of a cell, it provides shape to the cell.

Cell wall

• A cell wall is defined as the non-living component, covering the outmost layer of a cell.
• cell wall separates the interior contents of the cell from the exterior environment.
• It also provides shape, support, and protection to the cell and its organelles.

Nucleus

• A nucleus is defined as a double-membraned eukaryotic cell organelle that contains genetic material.
• It contains the cell’s hereditary information and controls the cell’s growth and reproduction
• It is responsible for coordinating many of the important cellular activities such as protein synthesis, cell division, growth, and a host of other important functions.

Ribosomes

• The ribosome is a complex molecule made of ribosomal RNA molecules and proteins that form a factory for protein synthesis in cells.

Additional Information  Cell was discovered by Robert Hooke in 1665, the cell has a rich and interesting history that has ultimately given way to many of today's scientific advancements.

The correct answer is ​Red and yellow soil.

Key Points

• Red and Yellow Soil:
  • Red soil develops on crystalline igneous rocks in areas of low rainfall in the eastern and southern part of the Deccan Plateau. Hence option 1 is correct.
  • Along the piedmont zone of the Western Ghat, a long stretch of area is occupied by red loamy soil.
  • Yellow and red soils are also found in parts of Odisha and Chhattisgarh and in the southern parts of the middle Ganga plain.
  • The soil develops a reddish colour due to a wide diffusion of iron in crystalline and metamorphic rocks.
  • It looks yellow when it occurs in a hydrated form.
  • The fine-grained red and yellow soils are normally fertile, whereas coarse-grained soils found in dry upland areas are of poor infertility.
  • They are generally poor in nitrogen, phosphorous and humus.

CONCEPT:

• Power is the ability to bend light and it is equal to the reciprocal of the focal length of the lens/mirror in meters.

Power (P) = 1/f

Where f is the focal length of the lens/mirror.

EXPLANATION:

As explained above, Dioptre is a unit of measurement of the optical power of a lens or curved mirror, which is equal to the reciprocal of the focal length measured in metres.

And since the S.I unit of the focal length is the meter (m).

So the S.I unit of power = 1/(SI unit of focal length) = m-1 = Dioptre (D).

1 m-1 = 1 D

CONCEPT:

• Newton's first law states that an object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by any external force.
• Newton's Second Law of motion states that the rate of change of momentum of an object is proportional to the applied force in the direction of the force i.e.,

​ \(F = \frac{{dp}}{{dt}}\)

Where F = force applied, m = mass of the body, and a = acceleration produced.

• Newton's Third Law of Motion states that 'To every action, there is an equal and opposite reaction'.

EXPLANATION:

• The launching of a rocket illustrates Newton’s third law of motion. Therefore the option 1 is correct.
• Newton's Third Law of Motion states that 'To every action, there is an equal and opposite reaction'.
• So, when the rocket is ignited, it releases gases from its thrusters thereby creating a force that will push rocket upwards and it can gain extreme velocity using this principle.

• Newton's third law of motion is applicable irrespective of the nature of the forces. The forces of action and reactions may be mechanical, gravitational, electric, or of any other nature.
• Action and reaction always act on different bodies. If they acted on the same body, the resultant force would be zero and there could never be accelerated motion.
• The forces of action and reaction cannot cancel each other. This is because action and reaction, though equal and opposite, always act on different bodies and so cannot balance each other.
• No action can occur in the absence of a reaction.