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Which are the four main seasons of India?
The Indian Meteorological Department (IMD) has recognised four distinct seasons in India: Winter (December to early April), Summer or pre-monsoon (April to June/July), Monsoon or rainy/advancing monsoon (June to September), and Post-monsoon or retreating monsoon (October to December). The HimalayanRead more
The Indian Meteorological Department (IMD) has recognised four distinct seasons in India: Winter (December to early April), Summer or pre-monsoon (April to June/July), Monsoon or rainy/advancing monsoon (June to September), and Post-monsoon or retreating monsoon (October to December). The Himalayan states additionally experience two more seasons, autumn and spring, due to their more temperate climate.
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See lessDraw a labelled diagram of the structure of atmosphere.
The atmosphere has five main layers, arranged from the Earth's surface outward: Troposphere, Stratosphere, Mesosphere, Thermosphere, and Exosphere. The Troposphere (up to ~12 km) is where temperature decreases with altitude and all weather phenomena occur. The Stratosphere (up to 50 km) contains theRead more
The atmosphere has five main layers, arranged from the Earth’s surface outward: Troposphere, Stratosphere, Mesosphere, Thermosphere, and Exosphere. The Troposphere (up to ~12 km) is where temperature decreases with altitude and all weather phenomena occur. The Stratosphere (up to 50 km) contains the ozone layer and is ideal for flying aeroplanes. The Mesosphere (up to 80 km) is where temperature again decreases with altitude and meteorites burn up. The Thermosphere (80–700 km) has rapidly rising temperature and contains the ionosphere, where auroras occur. The Exosphere is the outermost layer with very thin air, where light gases escape into space. (A labelled diagram showing these layers with increasing height on the vertical axis should be drawn, marking the boundaries: tropopause, stratopause, and mesopause.)
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What is atmosphere? Explain its composition with the help of a pie diagram.
The atmosphere is the layer of gases surrounding the Earth, held by gravity, and vital for the survival of living beings. It is composed mainly of nitrogen (78%) and oxygen (21%), along with small amounts of argon (0.93%), carbon dioxide (0.04%), and other gases (0.03%) including water vapour and duRead more
The atmosphere is the layer of gases surrounding the Earth, held by gravity, and vital for the survival of living beings. It is composed mainly of nitrogen (78%) and oxygen (21%), along with small amounts of argon (0.93%), carbon dioxide (0.04%), and other gases (0.03%) including water vapour and dust particles. Nitrogen and oxygen together make up about 99% of the atmosphere, while the remaining gases, though present in small quantities, play important roles such as trapping heat (carbon dioxide) and supporting cloud formation and precipitation (water vapour). The composition also varies with altitude.
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See lessShow that the triangle formed by a chord and the centre of the circle is isosceles.
Let AB be a chord and O be the centre of the circle. Join OA and OB. Since OA and OB are radii of the same circle, they are equal in length. A triangle having two equal sides is an isosceles triangle. Therefore, the triangle formed by the chord and the centre of the circle is an isosceles triangle.Read more
Let AB be a chord and O be the centre of the circle. Join OA and OB. Since OA and OB are radii of the same circle, they are equal in length. A triangle having two equal sides is an isosceles triangle. Therefore, the triangle formed by the chord and the centre of the circle is an isosceles triangle.
For more NCERT Solutions for Class 9 Maths Ganita Manjari Chapter 5 I’m Up and Down and Round and Round (2026-27):
https://www.tiwariacademy.com/ncert-solutions/class-9/maths/ganita-manjari-chapter-5/
See lessShow that if two such isosceles triangles (occurring in the previous question) have equal base length, they are congruent to each other.
Consider two triangles formed by equal chords and the centre of the same circle. Each triangle has two sides equal to the radii of the circle, and the given base lengths are also equal. Thus, all three corresponding sides of the triangles are equal. Therefore, the triangles are congruent by the SSSRead more
Consider two triangles formed by equal chords and the centre of the same circle. Each triangle has two sides equal to the radii of the circle, and the given base lengths are also equal. Thus, all three corresponding sides of the triangles are equal. Therefore, the triangles are congruent by the SSS Congruence Criterion.
For more NCERT Solutions for Class 9 Maths Ganita Manjari Chapter 5 I’m Up and Down and Round and Round (2026-27):
https://www.tiwariacademy.com/ncert-solutions/class-9/maths/ganita-manjari-chapter-5/
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