Science for Grade 2
1 Introduction to Science
1-1 What is Science?
1-2 Importance of Science in Everyday Life
1-3 Basic Scientific Tools and Equipment
2 The Living World
2-1 Living and Non-Living Things
2-2 Characteristics of Living Things
2-3 Plants
2-3 1 Parts of a Plant
2-3 2 Functions of Plant Parts
2-3 3 Types of Plants
2-4 Animals
2-4 1 Types of Animals
2-4 2 Characteristics of Different Animals
2-4 3 Animal Habitats
3 The Human Body
3-1 Parts of the Human Body
3-2 Functions of Body Parts
3-3 Basic Needs of Humans
3-4 Health and Hygiene
4 The Earth and Beyond
4-1 The Earth
4-1 1 Earth’s Surface
4-1 2 Land and Water Forms
4-2 The Sky
4-2 1 Sun, Moon, and Stars
4-2 2 Day and Night
4-2 3 Weather and Seasons
5 Materials and Their Properties
5-1 Types of Materials
5-2 Properties of Materials
5-3 Changes in Materials
5-4 Recycling and Conservation
6 Forces and Motion
6-1 What is a Force?
6-2 Types of Forces
6-3 Motion
6-4 Simple Machines
7 Energy and Its Forms
7-1 What is Energy?
7-2 Types of Energy
7-3 Sources of Energy
7-4 Energy Conversion
8 Simple Experiments and Observations
8-1 Importance of Experiments
8-2 Basic Scientific Method
8-3 Simple Experiments to Observe Scientific Concepts
9 Safety in Science
9-1 Importance of Safety
9-2 Safety Rules in the Science Lab
9-3 Handling Equipment and Materials Safely
Day and Night

Day and Night

1. Earth's Rotation

The Earth spins around its axis, which is an imaginary line that runs from the North Pole to the South Pole. This spinning motion is called rotation. It takes about 24 hours for the Earth to complete one full rotation, which is why we have day and night.

Imagine the Earth as a big spinning top. Just as a spinning top turns around its center, the Earth spins around its axis, creating day and night.

2. Day

Day is the period when a part of the Earth faces the Sun. During this time, we experience light and warmth. The Sun's rays reach the Earth's surface, allowing us to see clearly and perform our daily activities.

Think of day as the time when the Sun is shining brightly, like when you turn on the lights in your room. It's the time when everything is visible and active.

3. Night

Night is the period when a part of the Earth is turned away from the Sun. During this time, we experience darkness. The Sun's rays do not reach the Earth's surface, making it difficult to see without artificial light.

Imagine night as the time when you turn off the lights in your room. It's the time when everything is dark, and you need a flashlight or nightlight to see.

4. Time Zones

Because the Earth is divided into 24 time zones, different parts of the world experience day and night at different times. Each time zone is 15 degrees of longitude wide, and they help us coordinate our activities across the globe.

Think of time zones as different slices of a pizza. Each slice represents a different time zone, and as the Earth spins, each slice gets a turn to face the Sun, creating different times of day and night around the world.