History of the Universe Pretest

Scientists theorize that the portion of the universe visible today expanded explosively from a hot, dense mass about 14 billion years ago. What is evidence for this “big bang”?

• tides on Earth caused by the big bang’s gravitational forces

• volcanoes on Venus, which erupt because of the force of the “big bang”

• cosmic background radiation, which is energy left over from the big bang

• the formation of black holes caused by the collapse of very hot dense massive stars

Edwin Hubble was one of the most important scientists in our history.

What was his important discovery that provided evidence for the Big Bang Model?

• He observed redshift in the spectra of distant galaxies.

• He found evidence that the Milky Way is a spiral galaxy.

• He found evidence that the solar system formed from a nebula.

• He observed that the closer a galaxy is to our galaxy, the faster it is moving away.

Astronomers examine the spectra of a distant galaxy and see that it displays a red shift. What does this mean about the motion of the galaxy?

• The galaxy is not moving.

• The galaxy contains mostly red giant stars.

• The galaxy is moving towards Earth.

• The galaxy is moving away from Earth.

Scientists have found cosmic background radiation in the sky coming from deep space. What does this provide evidence for?

• The big bang theory, which says that the universe expanded rapidly from a hot, dense mass.

• The nebular hypothesis, which states that the Solar System formed from a cloud of dust and gas.

• The law of gravity, which states that objects with mass (including deep space objects) attract each other.

• Plate tectonic theory, which states that the Earth’s surface is made up of separate pieces that move relative to each other.

Edwin Hubble was one of the most important scientists in history. What important discovery did Hubble make that provided direct evidence that the universe is expanding?

• The light from distant galaxies is brighter that the light from closer galaxies, which means that they are moving toward our galaxy.

• The light from distant galaxies is shifted toward the blue end of the spectrum, which means that they are moving toward our galaxy.

• The light from distant galaxies is dimmer that the light from closer galaxies, which means that they are moving away from our galaxy.

• The light from distant galaxies is shifted toward the red end of the spectrum, which means that they are moving away from our galaxy.

If astronomers examine the spectral lines of a distant galaxy and saw that they displayed a blue shift, what would this mean about the motion of the galaxy?

• The galaxy is not moving.

• The galaxy is moving toward Earth.

• The galaxy is moving away from Earth.

• The galaxy is shifting back and forth at 650 Thz, the frequency of blue light.

What role did the force of gravity have in the formation of the universe?

• The force of gravity pulled atoms together to form clouds, which eventually became stars.

• The force of gravity was responsible for causing the Big Bang.

• The force of gravity caused stars to begin to orbit planets like Earth.

• The force of gravity made the universe stop expanding.

What technology has provided evidence for our current theory about the formation of the universe?

• Space probes have visited different planets and returned to Earth with samples to analyze.

• Computer modeling has been used to determine the way that the first stars caused the Big Bang when they collapsed into black holes.

• Particle accelerators smash particles into each other to determine the way that particles will act on Earth.

• Radio, visual, and x-ray telescopes have collected information from the entire range of the electromagnetic spectrum.

What is the existence of cosmic background radiation evidence for?

• energy left over from the big bang

• nuclear power plants

• remnants of radiation from nuclear tests during the Cold War

• the formation of black holes caused by the collapse of very hot, dense, massive stars

What is the currently accepted approximate age of the universe?

• 100 billion years

• 13.7 billion years

• 2,015 years

• 7 billion years