Exploring the Cosmos - Class Test 2 - Particles, Forces & the Big Bang
1. The size of the observable universe is
93 billion light years.
not known.
infinite.
13.7 billion light years.
2. The cosmological principle states that
the universe is expanding.
time is relative to the observer’s frame of reference.
if viewed on sufficiently large scales, the properties of the Universe are the same for all observers.
planets move in elliptical orbits.
3. The sky is dark at night because
the universe is expanding.
the light from very distant stars has not had time to reach us.
far away stars don't emit light in the visible spectrum.
dust obscures the light from far away stars.
4. Light from distant stars is shifted to the red end of the spectrum because…
these stars are very old.
the stars are moving away from us.
the galaxy is rotating.
it must pass through intervening dust clouds.
5. The Cosmic Microwave Background Radiation is
light emitted from binary pulsars.
light emitted from the surface of last scattering.
radio interference caused by roosting pigeons.
caused by cosmic rays in the upper atmosphere.
6. Eudoxus created a system of 27 concentric spheres to carry heavenly bodies in order to explain
the lack of annual parallax in the celestial sphere.
the phases of the moon.
retrograde motion.
the tides.
7. Aristotle believed that
the Earth is at the centre of the solar system.
Jupiter has moons.
the stars are Suns just like our own.
the Sun is at the centre of the solar system.
8. Newton's Theory of Gravity explains
Kepler’s Laws.
the force of magnetism.
the motion of Cepheid variable stars.
sun-spots.
9. Which of the following statements regarding the Grand Unified Theory is correct?
The GUT is a theory that shows physical laws are obeyed everywhere in the universe.
The GUT is a theory of everything.
The GUT can tell us what happened at the moment of birth of the universe.
The GUT is a theory that unifies 3 out of the 4 forces of nature.
10. Which of the following statements is true?
Photons can only be created by annihilating electrons with positrons.
Photons and electrons exert an attractive force
Photons are Fermions.
Photons mediate the electromagnetic force.
11. During the electroweak era, there were
photons, quarks and protons.
positrons, neutrinos and leptons
bosons, atoms and anti atoms.
gravitons, electrons and nuclei.
12. "Cosmic inflation" refers to
the increase in temperature as we approach, backward in time, the Big Bang.
the very early universe undergoing a sudden and massive expansion.
the fact that the expansion of the universe seems to be accelerating.
the increase of the wavelength of light as we look deeper into space.
13. The electron is an example of a
quark.
lepton.
boson.
gluon.
14. Which force is the weakest in nuclei?
Gravity.
Electromagnetism.
The strong force.
The weak nuclear force.
15. What binds protons and neutrons into nuclei?
Gravity.
The strong force.
The weak nuclear force.
Surface tension.
16. Which of the following eras came earliest in the history of the universe?
The electroweak era.
The era of atoms.
The era of nucleosynthesis.
The era of galaxies.
17. Which of the following observations is evidence of the presence of dark matter?
Distant galaxies are moving faster away from us.
Some stars appear to be moving towards us.
Distant supernovae appear dimmer.
Galaxies are spinning faster than expected.
18. Which of the following statements is false?
The mass of a particle is exactly the same as that of its antiparticle.
The antiparticle of an electron is a positron.
The antiparticle of a photon is a phonon.
The antiparticle of a gluon is a gluon.
19. The gravitational lensing effect is
why objects behind a strong gravitational field appear closer.
large telescopic lenses being formed using gravity.
lenses formed when a thin layer of fluid over an aperture sinks under its own weight.
the bending of light rays by a massive object.
20. Which of the following correctly ranks the forces in ascending order of relative strength?
Electromagnetism, weak, strong.
Weak, strong, gravity.
Gravity, weak, electromagnetism.
Weak, strong, electromagnetism.
21. The electron is an example of a
boson.
quark.
gluon.
lepton.
22. When was the microwave background radiation created?
The era of atoms.
The Grand Unified Theory era.
The era of Nucleosynthesis
The era of nuclei.
23. Today we know that the Milky Way has two disk components. Which of the following statements is correct?
The stars in the thick disc have an iron to oxygen ratio that suggests they were formed later than the thin disk.
The stars of the two disc components move in opposite direction around the galactic centre.
The stars of the thin disk have a stronger oscillatory motion than stars in the thick disc.
The stars in the thin disc have an iron to oxygen ratio that suggests they were formed later than the thick disk.
24. An S0 galaxy can evolve into which of the following galaxy types?
Galaxies cannot evolve from one type into another.
SBb
Sc
Sa
25. Which part of our galaxy features strong star formation?
Globular clusters
Halo
Central bulge
Spiral arms
26. Which of the following statements is not correct?
The central bulge is thicker than the galactic disk.
Our Galaxy has two disks.
Open clusters are mainly found in the disk.
The halo components move in nearly circular orbit around the centre of the galaxy.
27. Which of the following characteristics is true for elliptical Galaxies?
In elliptical galaxies there is very little active star formation.
Lots of interstellar medium is present in elliptical galaxies.
Elliptical galaxies often rotate fast.
Elliptical galaxies mainly feature Population I stars.
28. Which of the following galaxy types belongs to the barred spiral galaxies?
SBa
S0
Sb
E4
Submit Quiz