Physics · Science General

Astronomy and Cosmology

4,450 Questions

This topic provides questions on astronomy, cosmology, and the physical universe. It covers subjects like the Hubble sequence, constellations, dark matter, and stellar evolution. These questions help build a strong foundation for general science exam sections.

Galaxies and clustersConstellations and starsStellar evolutionSpace observatories

Astronomy and Cosmology Questions

Multiple choice evs our earth and the space asteroids, comets, and meteors and meteorites other objects in solar system asteroids, comets and meteors

Fill in the blank:

A shooting star is a _______.

  1. comet

  2. meteor

  3. meteorite

  4. none of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Shooting stars look like stars that quickly shoot across the sky, but they are not stars. A shooting star is really a small piece of rock or dust that hits Earth's atmosphere from space. It moves so fast that it heats up and glows as it moves through the atmosphere. Shooting stars are actually what astronomers call meteors. Most meteors burn up in the atmosphere before they reach the ground. However, once in a while a meteor is large enough than some of it survives and reaches Earth's surface. Then it is called a meteorite.
Hence, shooting star is a common name for the visible path of a meteoroid as it enters the atmosphere, becoming a meteor.

Multiple choice physics movement of the earth properties of stars life cycle of stars solar system and its planets types of galaxies galaxies

Why does sun appear larger than other stars to us?

  1. It is larger than other stars.

  2. It is farther than other stars.

  3. It is closer than other stars.

  4. It is faster than other stars.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sun is much closer to us as compared to other stars. Hence, it subtends larger angle at eyes compared to other stars and appear larger. Note that many stars are much larger than sun in size.

Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

The evidence for the rotation of stars comes mainly from the.

  1. Stark effect

  2. Photoelectric effect

  3. Doppler effect

  4. Zeeman effect
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The Doppler effect causes shifts in the spectral lines of a rotating star. As one side of the star rotates toward the observer and the other away, the light is blueshifted and redshifted respectively, causing spectral line broadening.

Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

What is happening inside a star while it expands into a subgiant?

  1. It is fusing hydrogen into helium in the core.

  2. It is fusing hydrogen into helium in a shell outside the core.

  3. It is fusing helium into carbon in the core.

  4. It is fusing helium into carbon in a shell outside the core.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fusion reactions take place and all hydrogen gets fuses to helium, thereby depleting hydrogen completely

Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

Which two energy sources can help a star maintain its internal thermal pressure? 

  1. nuclear fusion and gravitational contraction

  2. nuclear fission and gravitational contraction

  3. chemical reactions and gravitational contraction

  4. nuclear fusion and chemical reactions
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Fusion reaction happen on star   such as sun where hydrogen combine to form $He$ a fusion reaction releasing energy and gravitational contraction occur due to very high gravitational pull.

Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

What happens when a star exhausts its core hydrogen supply?

  1. Its core contracts, but its outer layers expand and the star becomes bigger and brighter.

  2. It contracts, becoming smaller and dimmer.

  3. It contracts, becoming hotter and brighter.

  4. It expands, becoming bigger but dimmer.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase.

When they reach this phase, hydrogen in them almost becomes depleted off and they become brighter and hotter and becomes low-mass white dwarfs

Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

Which of the following properties make flare stars so active?

  1. fast rotation rates

  2. deep convection zones

  3. convecting cores

  4. both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Flare stars have deep convection zone which help in rapid transition of energy produced in the star and also has convecting cores thus both deep convection zone and convecting cores make flare stars so active.

Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

Which of the following sequences correctly describes the stages of life for a low-mass star? 

  1. red giant, protostar, main-sequence, white dwarf

  2. protostar, main-sequence, red giant, white dwarf

  3. protostar, red giant, main-sequence, white dwarf

  4. protostar, main-sequence, white dwarf, red giant
Reveal answer Fill a bubble to check yourself
C Correct answer
Multiple choice physics life cycle of stars evolution and end stages of stars the stars stars

Which of the following stars will certainly end its life in a supernova? 

  1. the Sun

  2. a red giant star

  3. a 10-solar-mass star

  4. a neutron star
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Supernova being the last stages of a star, will happen only if the mass of the star exceeds the solar mass and hence a 10 solar mass star will have a high probability of becoming a supernova