Gravity in the Universe

​ I CAN complete this quizizz with a 80% or above

IN ORDER TO evaluate my understanding of Unit 4

BY HIGHLIGHTING the origin, composition, and forces of the universe.

Unit 4: Origin, Composition, and Forces of the Universe

Open Ended

What have you learned throughout this unit?

Answer the following questions as you comple this lesson:

• What role does gravity play in the formation and motion of celestial objects?

• How can we observe the effects of gravity on earth?

• What evidence shows that the universe is expanding?

• What provides information about objects in the universe?

​

Essential Questions

Gravity plays a major role in our universe.​ It is an attractive force that pulls objects together to keep planets in orbit around the sun, fuses together elements to create celestial objects, or pulls objects towards the center of the Earth. An objects gravitational pull depends on its mass and its distance.

• More mass, increased gravitational pull.

• Less mass, decreased gravitational pull

• Less distance, increased gravitational pull.

• More distance, decreased gravitational pull.

Gravity, Mass, Weight, and Distance

Mass is the amount of matter in an object. It is constant no matter the location.

Weight is the force acting on it due to acceleration due to gravity. It changes due to the gravitational pull of a location.

Mass vs Weight

Just because an object is visibly smaller, does not mean it has less mass or weigh less.

A bowling ball may be smaller than a beach ball but it contains more mass. Therefore, the bowling ball will be heavier than the beach ball.

W= mg

​Mass is measured in kilograms (kg)

Weight is measured in Newtons (N)

Multiple Select

Analyze the free-body diagrams. What can you infer about mass and weight n the different locations? Choose two statements.

• Mass and weight increase as you go to different locations.

• The weight increases on larger celestial objects and mass stays the same.

• The mass increases on larger celestial objects and weight stays the same.

• The sun has a larger gravitational pull than the other celestial objects.

Multiple Select

​Compare the following models. Which of the two (2) following statements are true regarding the force of gravity.

• Diagram A shows the force of gravity repelling the two objects.

• Diagram A shows a smaller force of gravity because the objects have a smaller mass.

• Diagram B shows the largest force of gravity because the objects have a larger mass and are close together.

• Diagram A shows the largest force of gravity because the objects are close together.

• Diagram C shows the largest force of gravity because the objects are far apart.

Fill in the Blank

What is the attractive force that plays a major role in the formation and motion of celestial objects in our universe?

Multiple Choice

What changes place to place due to the gravitational pull?

• Mass

• Distance

• Weight

• Gravity

Multiple Choice

What stays constant no matter the location?

• Mass

• Weight

• Distance

• Gravity

Tides provide evidence that the gravity can act over large distances.

• Spring tides occur when the Sun and the Moon work together to create a stronger gravitational pull.

  • the highest high and lowest low tides.

• Neap tides occur when the Sun and the Moon work against each other to create a weaker gravitational pull

  • the lowest high tides and highest low tides.

https://youtu.be/irPGBAsKxik

Spring Tides vs Neap Tides

​Use this link below to watch a video on tides.

​Spring tides vs Neap tides

Multiple Choice

When the Sun and the Moon line up at a perpendicular angle, what happens to the tides?

• The highest high and the highest low tides occur

• The highest highs and the lowest low tides occur.

• The lowest high and the highest low tide occur.

• The lowest high and the lowest low tide occur.

Multiple Choice

Tides are proof that gravity can act over large distances.

• True

• False

​Approximately 14 billion years ago, the universe began from a point of singularity. There was no matter, no time, and no space. It was a single point that was infinitely hot and dense. It quickly expanded from a singular point to a large universe. As it expanded, it cooled and released electrons and particles, such as helium and hydrogen to form atoms. Atoms were pulled together by gravity to form matter, which makes up the celestial objects in the universe. This is how Earth and the Solar System were created. We have proof of the expansion because light is red-shifting. This is evidence that galaxies are moving away from each other and the universe is continuously expanding.

Rapid Expansion

Multiple Choice

Which statement provides evidence that supports the rapid expansion theory?

• Scientists observe a redshift of light that signifies that galaxies are moving away from one another.

• Scientists observe a blueshift of light that signifies galaxies are moving towards one another.

• The universe is slowly shrinking and we are losing galaxies.

• The galaxy is getting hotter

Shows us the way light is traveling.

REDSHIFT- traveling away

BLUESHIFT- traveling towards

Doppler Effect of Light

On a visible light spectra, absorption lines shifted towards the violet show a blue shift and absorption lines shifted towards the red show a redshift.

SPECTRA

Multiple Choice

The observed spectrum shows evidence of a shift in the light spectrum. What type of shift is being observed and what does it mean for the galaxies?

• No shift because these are not the same galaxies.

• Red-shift; this means that galaxies are moving towards us.

• Blueshift; this means that galaxies are moving towards us.

• Redshift; this means that galaxies are moving away from us.

Stars are spheres of burning gas held together by gravity. During nuclear fusion, gravity fuses hydrogen atoms together to form helium atoms. All stars go through the same first three stages.

1. Nebula- cloud of dust and gas held together by gravity

2. Protostar-nuclear fusion begins (light and heat produced)

3. Main Sequence-90% of stars are in this stage of their life cycle

The mass of a star determines the next stages. During accretion,(dusk and gas around a star) gravity pulls the objects together to form planets.

Life Cycle and Composition of Stars

Multiple Choice

What are the first three stages of a stars life in order?

• giant, supernova, blackhole

• main sequence, supergiant, white dwarf

• nebula, protostar, main sequence

• nebula, main sequence, black dwarf

Multiple Choice

What happens during nuclear fusion?

• Gravity fuses together hydrogen and helium atoms; light and heat is produced

• Gravity fuses elements together to form celestial objects

• A star explodes and releases particles into the universe.

• A star burns fuel and dies out.

Just as the visible light spectra shows how light travels, star spectra shows the composition of stars. Spectroscopes are devices that measure the spectrum of light. While helium and hydrogen are the most common elements found in stars, there are other elements that make up a star as well.

A shifted spectra shows which way the star is traveling.

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This star is composed of the elements hydrogen and helium.

Star Spectra

Multiple Choice

A spectroscope is tool that is used to

• see objects in far away galaxies

• show how the stars are moving toward each other

• show the composition of stars with spectral lines

• see how stars go through different stages of life

Multiple Choice

Which elements are found in this star?

• hydrogen, calcium, and magnesium

• calcium, helium, and hydrogen

• hydrogen, helium, and magnesium

• magnesium, calcium, and helium

HR-diagrams show the luminosity or absolute magnitude (brightness) and surface temperature of stars according to its spectral class. There are four groups of stars on the HR-Diagram:

• white dwarfs (small/ low luminosity/high temperature)

• main sequence ( average/ high-low luminosity/ high-low temperature)

• giants (large/ average-high luminosities/ average-low temperatures)

• supergiants (largest/ high luminosities/ average-low temperatures)

The Sun is a main sequence star. It has an average surface tempurature and an average luminosity of 1.

​Hertzsprung Russell Diagrams (HR-Diagrams)

Multiple Choice

What does the Hertzsprung-Russell Diagram show?

• luminosity, apparent magnitude, and height of stars

• composition, luminosity, and death of stars

• temperature, size, and structure of stars

• luminosity, absolute magitude, and temperature of stars

Multiple Choice

A new star was discovered. It is very similar to our Sun in size and temperature. The star is using nuclear fusion to shine. Scientist would like to chart this star on the H-R diagram. Where on the H-R diagram does it belong?

• with the Red Supergiants

• on the main sequence

• as a white drawf

• as a neutron star

Fill in the Blank

Which star on the H-R Diagram would be the coolest and dimmest star?

Devices used to capture information about space without human intervention.

If destroyed, organizations can lose research.

Can travel further from Earth.

Unmanned

​Require human intervention to capture information about space.

Requires resources for human survival (food, oxygen, etc..)

Can not travel too far

Obtains research that can not be completed by unmanned explorations

Manned

​Manned vs Unmanned Space Exploration

Earth's atmosphere distorts the lights we see. The Hubble telescope is placed in orbit around Earth to explore the universe in visible, ultraviolet and infrared wavelengths.

Hubble Telescope

Measures the wavelength and frequency of light, and allows us to identify and analyze the atoms of a sample we place within it.

Spectroscope

Carry cameras and scientific sensors. They may gather information about Earth's land, air and water or collect data from the solar system and universe.

Satellites

Multiple Choice

Which statement is UNTRUE about unmanned space exploration?

• They provide services for and details about the Earth.

• They travel through space, far distances from Earth.

• They transport humans into space and bring back samples of other celestial object's surface.

• They take images of celestial objects.