Motions of the Earth Question and Answer | ICSE Class 7

This page provides detailed Motions of the Earth ICSE Class 7 Questions and answers to help students understand the topic better. The chapter explains the two main motions of the Earth—rotation and revolution—and their effects such as day and night, seasons, and the year. These solved Q&As are designed to clarify key concepts and assist Class 7 students in scoring higher in exams.

A. Tick the correct answers:

  1. The Earth rotates from west to east.
  2. The imaginary line that separates the lighted half of the Earth from the darker half is called the circle of illumination.
  3. When the South Pole is inclined towards the Sun, the North Pole experiences continuous night for 6 months.
  4. The day on which the midday Sun shines vertically overhead at the Tropic of Capricorn is called Winter Solstice.
  5. In the Northern Hemisphere, the Autumnal Equinox occurs on 23rd September.

B. Fill in the blanks:

  1. The speed of the Earth’s rotation at the poles is: zero.
  2. Which of the following is not caused due to the rotation of the Earth? Seasons.
  3. In which of the following years was/will be a leap year? 2012.
  4. Which of the following places enjoys equal day and night throughout the year? Equator.
  5. The longest day in the Southern Hemisphere is on: 22nd December.

C. Give reasons for the following:

  1. An additional day is added to the month of February in a leap year.

     Ans: The Earth takes 365 days, 5 hours, 48 minutes, and 56 seconds to complete one revolution. For convenience, we count only 365 days in a year. The balance of about 6 hours is adjusted by adding one extra day every four years. This additional day is added to the month of February, making 29 days in February and 366 days in that year. Such a year is called a leap year, and the extra day is called a leap day.
  2. The length of days and nights is not the same throughout the Earth.

    Ans: The length of days and nights is not the same throughout the Earth because of the inclination of the Earth’s axis. Due to this tilt, the Northern Hemisphere remains inclined towards the Sun for half of the year and the Southern Hemisphere for the other half.
    • When the Northern Hemisphere is tilted toward the Sun, more sunlight reaches it, causing longer days and shorter nights.
    • When the Southern Hemisphere is tilted toward the Sun, more sunlight reaches it, resulting in longer days and shorter nights in that region.
Look at the essay on A teacher takes a hand open a mind and touches a heart Essay
Also, look for the Study Guide of Globes and Maps

D. Answer the following questions:

  1. Mention three differences between rotation and revolution.

     Rotation:
     a. The Earth rotates on its axis from west to east, which is tilted at an angle of 66½ degrees with the Earth’s orbit.
    b. It causes day and night.
    c. It gives us a day of 24 hours.

    Revolution:
     a. The Earth revolves around the Sun from west to east at a speed of 30 km per second.
    b. It causes variations in the length of day and night and the phenomenon of seasons.
    c. The Earth takes 365¼ days to complete one revolution.
  2. What are the effects of the Earth’s rotation?

     Ans: The effects of the Earth’s rotation are:
    a. It causes bulging at the equator and flattening at the poles.
    b. It causes day and night.
    c. It gives us a 24-hour day.
    d. It provides the concept of direction based on sunrise and sunset.
    e. It causes the deflection of winds and ocean currents.
    f. It causes tides twice a day.
  3. What are the effects of the Earth’s revolution?

     Ans: The effects of the Earth’s revolution are:
    a. It causes variations in the length of day and night.
    b. It affects the distribution of heat on Earth’s surface.
    c. It leads to the occurrence of seasons.
  4. What is aphelion and perihelion? Mention the dates on which they occur.

    Ans:
    • When the distance between the Earth and the Sun is maximum (about 151 million km), the Earth is at aphelion. The word “aphelion” comes from “ap-” (away from) and “Helios” (the Sun).
    • When the distance between the Earth and the Sun is minimum (about 146 million km), the Earth is at perihelion. The word “perihelion” comes from “peri-” (near) and “Helios” (the Sun).
    • The Earth reaches perihelion on 4th January each year.
    • The Earth reaches aphelion on 4th July each year.
  5. Why is noon hotter than morning and evening?

     Ans: The Sun’s rays are almost vertical at noon, whereas they are slanting in the morning and evening. Vertical rays concentrate more heat in a smaller area, making noon hotter than morning and evening.
  6. What are the causes of the change of seasons?

     Ans: The change of seasons is caused by:
    a. The Earth’s rotation.
    b. The Earth’s revolution around the Sun.
    c. The inclination of the Earth’s axis.

    The year is divided into four seasons—Spring, Summer, Autumn, and Winter—due to these factors.

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