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Physics 0625

6. Space physics

The Earth and the Solar System, orbits, stars, the life cycle of stars and the expanding universe.

  1. 6.1

    Earth and the Solar System

    Day and night, seasons, the Moon, the planets, orbital speed and the formation of the Solar System.

    Full lesson1 questions2 cardsSimulation
    • 6.1.1Explain day, night and the apparent motion of the Sun in terms of the Earth's rotation.
    • 6.1.2Describe the Solar System, the order of the planets, and the role of gravity in orbits.
    • 6.1.3Recall and use v = 2πr / T for orbital speed.
  2. 6.2

    Stars and the Universe

    The Sun as a star, nuclear fusion, the life cycle of stars, galaxies, redshift and the Big Bang.

    Full lesson2 questions5 cardsReview first: 6.1
    • 6.2.1Describe the Sun as a star that releases energy by nuclear fusion of hydrogen into helium.
    • 6.2.2Describe the life cycle of a star, including the difference between low-mass and high-mass stars.
    • 6.2.3Describe redshift as evidence that the Universe is expanding.