This set of Engineering Physics Multiple Choice Questions & Answers (MCQs) focuses on “Cosmology”.
1. Cosmology is the branch of science concerned with the ____________
a) Formation of Planets
b) Formation of Stars
c) Formation of Universe
d) Formation of Black holes
Explanation: Cosmology is the branch of science which concerns with the creation of universe, from the big band theory, and with the eventual fate of the universe.
2. Evidence that much of the mass of the universe consist of dark energy has come from __________
a) measuring the density of matter in the solar system
b) determining the distance to the Coma cluster
c) determining the distance to quasars
d) observing extremely distant supernovae
Explanation: Supernovae are created when a massive star dies. By observing supernovae, which are at a very large distance, we have got the evidence that universe contains a majority of dark matter.
3. Which of the following is not an implication of Hubble’s law?
a) The universe is expanding
b) We are in the center of the universe
c) The universe had a beginning
d) The universe was once denser than it is now
Explanation: The Hubble states that the universe is expanding. It also implies that the universe had a beginning and that it was once denser than it is now. It does not state anything about the earth being at the center of the universe.
4. The expansion age of the universe is about _________
a) 1 billion years
b) 10 billion years
c) 100 billion years
d) 1000 billion years
Explanation: The universe is always expanding. According to the study, the universe has been expanding for about 10 billion years till now.
5. The rate of expansion of the universe is __________
Explanation: The universe is dominated by dark energy. Due to this, the rate of the expansion of the universe is accelerating.
6. The cosmic background radiation observed is starlight.
Explanation: The cosmic background radiation was produced about a million years after the beginning of the expansion. It is the brightest in the radio part of the spectrum.
7. Leptons and quarks are called the survivors.
Explanation: Leptons and quarks are called the survivors because they survived the big bang, which cause the beginning of the universe as we know it, and are still around today.
8. What will happen if the density of the universe is less than the critical density?
a) The Universe will contract
b) The Universe will contract and then rebound
c) The universe will stop expanding
d) The universe will keep expanding forever
Explanation: When the density of the nucleus is less than a certain critical density, the universe will keep expanding forever, like it is right now, till the end of the time.
9. The theory which believes that the universe works like a heart beating in rhythms is _________
a) Oscillating Universe Theory
b) Slowing down theory
c) Big crunch theory
d) Big bang theory
Explanation: The oscillating universe theory combines both the big bang theory and the big brunch theory. It states that the universe works like a heartbeat- first it starts expanding after the big bang and then it contracts like a big crunch and the process goes on again.
10. The brightest nebula in the sky is __________
Explanation: Nebula are the sites where the stars are created or are the remnants of a supernova explosion. The brightest nebula in the sky is Orion.
11. Most of the helium of the universe was produced __________
a) In stars
b) In quasars
c) At the time the cosmic background radiation was formed
d) First ten minutes of the expansion
Explanation: Helium is an important fuel for the fabrication and the working of stars. Most of the helium present in the universe today was produced during the first 10 minutes of the expansion.
12. The cluster of galaxies which is farthest from the Earth is __________
a) Abel 2218
b) Milky way
Explanation: The farthest observed cluster of galaxies from the Earth is Abel 2218. Milky way is our galaxy and Andromeda is a neighboring galaxy to our milky way.
13. Nova are thought to occur in a system, X, in which a white-dwarf star orbits a red giant star. What is X?
a) Triple System
b) Binary system
c) Compact system
d) Congenial system
Explanation: A binary system is the one where two stars orbit around a common center of mass. When a white-dwarf star orbits a red-giant star, novae are formed.
14. The brightest star in a constellation _________
Explanation: A constellation is a group of stars that form an imaginary line or pattern. The brightest star in a constellation is called the alpha while the star with the least brightness is called Omega.
15. A planet is orbiting a star. What is relation between Ta and Tb, given that the arc subtended on the path by the planet is same in both cases?
a) Ta = Tb
b) Ta < Tb
c) Ta < Tb
d) Insufficient information
Explanation: The closer the planet will be to the star, the higher will be its speed and the sooner it will cover the distance. The planet sweeps equal area in equal time intervals. As the area swept by B is higher, Ta > Tb.
Sanfoundry Global Education & Learning Series – Engineering Physics.
To practice all areas of Engineering Physics, here is complete set of 1000+ Multiple Choice Questions and Answers.