Space Physics and Astronomy - SS1 Physics Past Questions and Answers - page 3
Hubble's Law describes the relationship between the _______ of a galaxy and its _______.
Size, colour
Shape, age
Distance, velocity
Mass, luminosity
Hubble's Law states that the velocity at which a galaxy is moving away from us is proportional to its _______.
Temperature
Mass
Size
Distance
The expansion of the universe implies that galaxies are moving away from each other because _______.
They are attracted by gravity
They are pushed by dark matter
They are pushed by dark energy
They are influenced by magnetic fields
The discovery of the expanding universe was made by _______.
Edwin Hubble
Albert Einstein
Isaac Newton
Galileo Galilei
Hubble's constant represents the _______ of the universe.
Age
Temperature
Size
Rate of expansion
Explain Hubble's Law and its significance in understanding the expanding universe.
Hubble's Law states that the velocity at which a galaxy is moving away from us is proportional to its distance. This implies that the universe is expanding, with galaxies moving away from each other. Hubble's Law provides evidence for the Big Bang theory, suggesting that the universe originated from a single point and has been expanding ever since. It also helps determine the rate of expansion, known as the Hubble constant. Understanding Hubble's Law is crucial for unravelling the dynamics and evolution of the universe.
Describe the observational evidence that supports Hubble's Law and the expanding universe.
Observational evidence supporting Hubble's Law and the expanding universe comes from the redshift of distant galaxies. When light from a galaxy is observed, its wavelength appears stretched, shifting towards longer wavelengths. This redshift indicates that the galaxy is moving away from us. Moreover, the degree of redshift is directly proportional to the galaxy's distance, as stated by Hubble's Law. This consistent relationship between redshift and distance provides strong empirical evidence for the expanding universe and validates Hubble's Law.
According to the Big Bang theory, the universe originated from:
A massive explosion
The collision of two galaxies
The collapse of a giant star
A singularity of infinite density and temperature
The cosmic microwave background radiation is:
Radiation emitted by distant stars
Radiation emitted by black holes
Radiation left over from the early universe
Radiation emitted by the Sun
The discovery of the cosmic microwave background radiation provides strong evidence for:
The existence of black holes
The steady-state theory of the universe
The Big Bang theory
The presence of dark matter