Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Astrophysics
156 practice questions
Topics covered
Practice questions
131–140 of 156
Question 131
3 marks · Easy
Answer and see the solution →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)
Question 132
4 marks · Normal
Answer and see the solution →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)[2 marks]Explain why the absorption lines move towards the red end of the spectrum.
(b)[2 marks]Explain why the absorption lines move towards the red end of the spectrum.
Question 133
3 marks · Normal
Answer and see the solution →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 = )
Question 134
1 mark · Normal
Answer and see the solution →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?
Question 135
1 mark · Normal
Answer and see the solution →Which of the following statements does NOT support the Big Bang theory?
- A.Red-shift in the spectra of galaxies
- B.Cosmic microwave background radiation
- C.Observation that the universe is expanding
- D.Blue-shift in the spectra of galaxies
Question 136
2 marks · Normal
Answer and see the solution →Describe two pieces of evidence that support the Big Bang theory.
Question 137
2 marks · Normal
Answer and see the solution →Explain why the cosmic microwave background (CMB) radiation is an important piece of evidence for the Big Bang theory.
Question 138
3 marks · Normal
Answer and see the solution →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)[2 marks]Calculate the velocity of the galaxy relative to Earth. (Speed of light = 3.0 × 10^8 m/s)
(b)[1 mark]State whether the galaxy is moving towards or away from Earth.
Question 139
2 marks · Normal
Answer and see the solution →What is meant by the term ‘red-shift’ and what does it suggest about the universe?
Question 140
4 marks · Easy
Answer and see the solution →A student is looking at the light spectra from two galaxies, Galaxy A and Galaxy B, using a spectrometer. She notices that the absorption lines for Galaxy B are further towards the red end of the spectrum than those in Galaxy A.
(a)[2 marks]What is the name for the shift of absorption lines towards the red end of the spectrum, and what does it indicate about a galaxy’s motion relative to us?
(b)[2 marks]If Galaxy B’s absorption lines have shifted more than Galaxy A’s, what can you deduce about the relative speeds and distances of the two galaxies from us?