Free Practice Quiz Question List

6 Expansion of the Universe Online Quiz Questions

Use this free practice quiz with 20 questions to review 6 Expansion of the Universe, test your knowledge, and prepare for your next test or exam.

20 questions

True or false

1 point

True or false: The Big Bang model describes matter exploding from one location into pre-existing empty space.

A
True
B
False

True or false

1 point

True or false: H₀ is the present-day value of the Hubble parameter, not a rate that stays unchanged throughout cosmic history.

A
True
B
False

Fill in the blank

1 point

The stretching of traveling light caused by cosmic expansion is called .

Written response

1 point

In what year did Edwin Hubble publish evidence for a relationship between galaxy distance and recession?

Written response

1 point

Light is emitted when the scale factor is $a=\frac{1}{5}$ . Using $1+z=\frac{1}{a}$ , what is its redshift $z$ ?

Fill in the blank

1 point

The standard cosmological model estimates that the universe began expanding about years ago.

Choose one

1 point

Which value is conventionally assigned to the universe's scale factor today?

A
$a=0$
B
$a=1$
C
$a=1+z$
D
$a=H_0$

Choose one

1 point

For a relatively nearby galaxy, use $v\approx H_0d$ . If $H_0$ is about 70 km/s/Mpc and the galaxy is 80 Mpc away, what is its approximate average recession speed?

A
560 km/s
B
1,150 km/s
C
5,600 km/s
D
7,000 km/s

Choose one

1 point

What does the term “Hubble tension” refer to?

A
The stretching of light as the universe expands
B
A discrepancy between some measurements of the expansion rate
C
The acceleration of expansion attributed to dark energy
D
The limit on how quickly objects can move locally through space

Choose one

1 point

In the expanding-universe picture, what does it mean that sufficiently distant regions can separate at a rate greater than the speed of light?

A
It means distant galaxies locally travel through space faster than light.
B
It violates relativity because no separation rate can exceed the speed of light.
C
It can occur without distant regions locally moving through space faster than light.
D
It means the Hubble law is exact at every distance.

Choose all

1 point

Select all accurate statements about cosmic expansion on large scales.

A
On the largest scales, average distances between galaxies that are not gravitationally bound grow over time.
B
Galaxies, solar systems, and atoms all expand along with the universe.
C
An observer in any typical galaxy sees distant galaxies receding on average.
D
Earth must be at the center because distant galaxies recede from it.

Choose all

1 point

Select all statements that accurately describe the universe's expansion history and the standard model's account of recent acceleration.

A
Gravity from matter slowed expansion during much of cosmic history.
B
The late-1990s supernova observations showed that expansion had stopped.
C
Distant supernova observations in the late 1990s showed that expansion is accelerating in the more recent universe.
D
The standard model attributes the recent acceleration to ordinary motion through space alone.
E
In the standard model, dark energy is used to account for the acceleration.

Open ended

1 point

What does the standard model predict for the universe's far future if dark energy behaves like a constant cosmological constant, and why is that forecast not certain?

Choose one

1 point

As the universe expands, what happens to the size of a gravitationally bound solar system?

A
The solar system expands at the same rate as the average distance between unbound galaxies.
B
The solar system remains bound by gravity, so its size does not increase just because the universe expands.
C
The solar system is unaffected because cosmic expansion occurs only beyond the Milky Way.
D
The solar system expands only when Earth moves away from the center of the universe.

True or false

1 point

The Big Bang describes space expanding, rather than matter exploding from one location into pre-existing empty space.

A
True
B
False

Choose one

1 point

What is the name of the ancient light observed today that was released when the universe became transparent?

A
Hubble tension
B
Cosmological redshift
C
Cosmic microwave background
D
Dark energy

Choose one

1 point

A galaxy's light travels through expanding space. Setting aside any contribution from the galaxy's local motion, what effect does cosmic expansion have on the light?

A
Its wavelength is stretched, shifting it toward redder wavelengths.
B
Its wavelength is compressed, shifting it toward bluer wavelengths.
C
Its wavelength remains unchanged because only galaxies expand.
D
It becomes redshifted only if the galaxy is moving through space locally.

Written response

1 point

Use $1+z=\frac{1}{a}$ to calculate the redshift $z$ for light emitted when the scale factor was $a=\frac{1}{4}$ . Enter only the numerical value.

Choose one

1 point

Which statement best describes the Big Bang in the standard cosmological model?

A
It was an explosion from a central point into empty space.
B
It describes the expansion of space from an early hot, dense state.
C
It describes matter appearing at one location while space remained static.
D
It describes a brief expansion that ended when the universe became transparent.

Written response

1 point

What is the standard name for the ancient light observed today that became free to travel when the universe turned transparent?