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Pearson Edexcel International GCSE (9–1) · PHYSICS · Chapter

Cosmology

37 practice questions

Topics covered

Practice questions

21–30 of 37

  1. Question 21

    1 mark · Easy

    A scientist observes that the absorption lines in the spectrum of a distant galaxy have moved towards longer wavelengths than those from our Sun. State the name of this effect.

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  2. Question 22

    3 marks · Easy

    The universe is thought to have begun with a huge explosion called the Big Bang.

    (a)

    State one observation from distant galaxies that supports the idea that the universe is expanding.

    [1 mark]
    (b)

    Describe what the cosmic microwave background (CMB) radiation is.

    [2 marks]
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  3. Question 23

    3 marks · Easy

    Light from a distant galaxy has a wavelength of 660 nm. The same spectral line measured from our Sun is 600 nm. Calculate the speed at which the galaxy is moving relative to Earth. (Speed of light = m/s)

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  4. Question 24

    4 marks · Normal

    A scientist studies the light emitted from a nearby galaxy and observes that absorption lines have shifted compared to those from our Sun.

    (a)

    What is this phenomenon, and what does it tell us about the motion of the galaxy relative to Earth?

    (b)

    Explain why the absorption lines move towards the red end of the spectrum.

    [2 marks]
    (b)

    Explain why the absorption lines move towards the red end of the spectrum.

    [2 marks]
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  5. Question 25

    3 marks · Normal

    Light from a distant galaxy shows an absorption line at a wavelength of 650 nm, while the same line from our Sun is at 520 nm. Calculate the speed at which the galaxy is moving relative to Earth. (Speed of light = )

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  6. Question 26

    1 mark · Normal

    What is the name given to the type of electromagnetic radiation believed to be the afterglow of the Big Bang, detected from all directions in the universe?

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  7. Question 27

    1 mark · Normal

    Which of the following statements does NOT support the Big Bang theory?

    1. A.Red-shift in the spectra of galaxies
    2. B.Cosmic microwave background radiation
    3. C.Observation that the universe is expanding
    4. D.Blue-shift in the spectra of galaxies
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  8. Question 28

    2 marks · Normal

    Describe two pieces of evidence that support the Big Bang theory.

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  9. Question 29

    2 marks · Normal

    Explain why the cosmic microwave background (CMB) radiation is an important piece of evidence for the Big Bang theory.

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  10. Question 30

    3 marks · Normal

    Light from a galaxy is measured, and the absorption lines are found to be shifted by 200 nm compared to the reference wavelength of 500 nm on Earth.

    (a)

    Calculate the velocity of the galaxy relative to Earth. (Speed of light = 3.0 × 10^8 m/s)

    [2 marks]
    (b)

    State whether the galaxy is moving towards or away from Earth.

    [1 mark]
    Answer and see the solution →