D. Answer the following
1. Name the layers of the Earth.
2. Why is the magnetic field of the Earth important?
3. What are the phases of the Moon? How do they occur?
4. Describe the solar eclipse with the help of a diagram.
5. Why do we see only one side of the Moon?
Picture study
it in handening. Describe
Answers
Answer:
1 The earth is made up of three different layers: the crust, the mantle and the core.
Teachers resources: Earth Science Ireland - Planet EarthRelated publications: Understanding
2 The rotation of Earth on its axis causes these electric currents to form a magnetic field which extends around the planet. The magnetic field is extremely important to sustaining life on Earth. Without it, we would be exposed to high amounts of radiation from the Sun and our atmosphere would be free to leak into space.
3 From Earth we see the Moon grow from a thin crescent to a full disk (or full moon) and then shrink back to a thin crescent again before vanishing for a few days. The Moon phases are produced by the alignment of the Moon and the Sun in the sky. The lit part of the Moon always points the way to the Sun.
4 solar eclipse occurs when a portion of the Earth is engulfed in a shadow cast by the Moon which fully or partially blocks sunlight. This occurs when the Sun, Moon and Earth are aligned. Such alignment coincides with a new moon (syzygy) indicating the Moon is closest to the ecliptic plane.
5 The Moon orbits Earth once every 27.3 days and spins on its axis once every 27.3 days. This means that although the Moon is rotating, it always keeps one face toward us. Known as “synchronous rotation,” this is why we only ever see the Moon's nearside from Earth.