Space Physics and Astrophysics - SS2 Physics Past Questions and Answers - page 4
The relationship described by Hubble's Law is expressed mathematically as:
v = H0/d
v = c/f
v = λf
v = mgh
v = H0/d (where v is the recession velocity, H0 is Hubble's constant, and d is the distance)
The interpretation of Hubble's Law suggests that the universe is:
Contracting
Oscillating
Expanding
Static
Hubble's Law is based on the observation of the:
Cosmic microwave background radiation
Redshift of distant galaxies
Formation of supernovae
Gravitational lensing effect
The discovery of the expanding universe supports the concept of the:
Big Bang theory
Steady-state theory
Pulsating universe theory
Multiverse theory
Hubble's Law implies that objects farther from Earth have:
Higher redshifts
Slower recession velocities
Larger apparent sizes
Higher luminosities
Hubble's Law provides a basis for estimating the:
Age of the universe
Temperature of the cosmic microwave background
Mass of supermassive black holes
Density of dark matter
Explain Hubble's Law and its significance in understanding the expanding universe.
Hubble's Law states that the recession velocity of a galaxy is directly proportional to its distance from Earth. This means that the farther a galaxy is from us, the faster it is moving away. Hubble's Law provided strong evidence for the concept of an expanding universe. It implies that the universe is not static but rather undergoing continuous expansion. The law also led to the development of the Big Bang theory, which suggests that the universe originated from a singularity and has been expanding ever since. Hubble's Law allows astronomers to estimate the distances and velocities of galaxies, providing insights into the structure, age, and evolution of the universe.
Discuss the observational evidence that supports Hubble's Law and the expanding universe.
There are several pieces of observational evidence that support Hubble's Law and the expanding universe. One crucial piece of evidence is the observation of the redshift of light from distant galaxies. Redshift occurs when light from an object is stretched, causing its wavelength to increase. This stretching of light is due to the expansion of space itself. The degree of redshift observed in galaxies is directly correlated with their distances from us, confirming the relationship described by Hubble's Law.
Another supporting evidence is the isotropy and homogeneity of the universe on a large scale. Observations show that, on average, galaxies are distributed uniformly in all directions, indicating a homogeneous distribution. This supports the idea that the universe is expanding uniformly in all directions, as predicted by the expanding universe model.
Additionally, the cosmic microwave background radiation (CMB) provides strong evidence for the Big Bang and the expanding universe. The CMB is a faint, uniform radiation that permeates the entire universe and is considered the afterglow of the early hot and dense stages of the universe. The observed pattern of the CMB supports the idea that the universe was once much denser and hotter and has been expanding since its inception.
According to the Big Bang Theory, the universe originated from:
A massive explosion
The collapse of a previous universe
A singularity
The collision of multiple galaxies
The cosmic microwave background radiation (CMB) is:
Radiation emitted by stars in the Milky Way galaxy
Radiation emitted by distant quasars
Radiation from the Sun
Radiation from the early stages of the universe