Physica Science - Module 11

Question 1

What are the four fundamental Forces of Creation?

Answer 1

1) The Gravitational Force
2) The Electromagnetic Force
3) The Weak Force
4) The Strong Force

Question 2

Gravitational Force

Answer 2

• Any two objects that have mass are attracted to one another via the gravitational force.
• The weakest of the fundamental forces
• The force is attractive only.

Question 3

Electromagnetic Force

Answer 3

• Exists between particles with an electric charge.

- The Force can be either attractive or repulsive.

Question 4

Weak Force

Answer 4

• Governs certain radioactive processes in atoms

Question 5

Strong Force

Answer 5

• Responsible for holding the center of the atom (the nucleus) together.
• Strongest force we know of.

Question 6

What two forces are usually combined by scientists to make 3 rather than 4 fundamental forces?.

Answer 6

Electromagnetic and Weak = Electroweak Force

Question 7

Why do scientists combine Electromagnetic Force and Weak Force to make the Electroweak Force?

Answer 7

Physicists have used a variety of mathematical models and experimental results to show that the electromagnetic force and the weak force are different facets of the same force.

Question 8

Three general principles of the Universal Law of Gravitation.

1) Key word - attract
2) Key word - mass
3) Key word - distance

Answer 8

1) All objects with mass are attracted to one another by the gravitational force.
2) The gravitational force between two masses is directly proportional to the mass of each object.
3) The gravitational force between two masses is inversely proportional to the square of the distance between those objects.

Question 9

What does the first principle of the gravity mean?

“All objects with mass are attracted to one another by the gravitational force.”

Answer 9

All matter is attracted to all other matter.

All matter is attracted to the earth.

The earth is attracted to the sun, etc.

Question 10

What does “universal” mean?

Answer 10

It applies to anything/everything in the universe.

Question 11

What does the second principle of gravity mean?

“The gravitational force between two masses is directly proportional to the mass of each object.”

Answer 11

Proportional = the bigger the mass, the bigger the force

The strength of the gravitational force between two object increases as the mass of either increases.

Question 12

What does the third principle of gravity mean?

“The gravitational force between two masses is inversely proportional to the square of the distance between those objects.”

Answer 12

Inversely proportional = When the distance is small, the force is big; when the distance is big, the force is small.

The strength of the gravitational force between two objects increases as the objects gets closer; the strength of the gravitational force between two objects decreases as the objects get further away.

Question 13

Centripetal Force

t f n t m a o m i a c.
i i d p t t v o t o, w m i p t t c o t c

Answer 13

The force necessary to make an object move in a circle. It is directed perpendicular to the velocity of the object, which means it points toward the center of the circle.

Question 14

Three general principles regarding centripetal force:

1) Key word - requires
2) Key word - large force / fast object
3) Key word - large force / small circle

Answer 14

1) Circular motion requires centripetal force.
2) The larger the centripetal force, the faster an object travels in a circle of the given size.
3) At a given speed, the larger the centripetal force, the smaller the circle.

Question 15

If two objects move from being 10 cm apart to being 5 cm apart, how do you figure out the difference in force?

Hint = Third Principle of Gravity.

Answer 15

1) What did you do to the first measurement to get the second measurement? Divide by 2
2) Use the opposite (inverse) operation - Multiply = more.
3) Square the number - 2 squared = 4.
4) So the force of gravity is 4 times more than before.

Question 16

If two objects (3 kg and 5 kg) are replaced by two other objects (1 kg and 10 kg), how do you figure out the difference in force?

Hint = Second Principle of Gravity.

Answer 16

1) What did you do to the measurement of the first object? Divide by 3
2) What did you do to the measurement of the second object? Multiply by 2
3) The force of gravity is 1/3 x 2 = 2/3 less force (because the divide by number is greater than the multiply by number)

Question 17

Centripetal Acceleration

Answer 17

An object’s acceleration even though the SPEED is not changing.

Question 18

Circular motion requires what?

Answer 18

Centripetal force.

Question 19

What is an asteroid called that is in the earth’s orbit?

Answer 19

a meteoriod

Question 20

What is an asteroid called that hits the earth’s atmosphere and heats to white hot?

Answer 20

a meteor

Question 21

What is an asteroid called that hits the earth?

Answer 21

a meteorite

Question 22

What are “dirty snowballs” called?

Answer 22

Comets

Question 23

How did comets get the nickname of “dirty snowballs”?

Answer 23

They are mostly composed of dust grains, chunks of dirt, and ice. The ice is frozen water, frozen carbon dioxide, frozen ammonia, and frozen methane.

Question 24

What are the three main parts of a comet?

Answer 24

Core/nucleus - “dirty snowball”

Coma - the “fuzzy” atmosphere around the core

Tail - The solar wind blowing the particles away from the coma.

Question 25

What is the Oort Cloud?

Answer 25

A hypothetical (supposed) shell of icy bodies that surrounds the solar system.

Proposed by Jan Oort.

Question 26

What is the Kuiper Belt?

Answer 26

A band of comet material that exists just beyond Neptune from which is supposed to be the origin of some short-period comets.

Proposed by Gerard Kuiper.

Question 27

What are the three criteria for being a planet?

Answer 27

1. A planet must be in orbit around the sun.
2. A planet must be nearly round in shape.
3. A planet must have “cleared the neighborhood” around it’s orbit.

Question 28

What are the four criteria for being a dwarf planet?

Answer 28

1. A dwarf planet must be in orbit around the sun.
2. A dwarf planet must be nearly round in shape.
3. A dwarf planet has not “cleared the neighborhood” around its orbit.
4. A dwarf planet is not a satellite.

Question 29

What are the names of 3 of the known dwarf planets?

Answer 29

Pluto, Eris, and Ceres

Question 30

What is a KBO?

Answer 30

Kuiper Belt Object

Question 31

In 2006, who proposed that there be a new definition of a planet?

Answer 31

The International Astronomical Union

Question 32

What is the General Theory of Relativity?

Answer 32

A broad theory the attempts to explain an entire way of looking at physics.

One byproduct is an original explanation of what causes the gravitational force - space bends in the presence of an object with mass.

Proposed by Albert Einstein in 1916.

Question 33

What is the Graviton Theory of Gravity?

Answer 33

A theory of gravity that says that two massive objects tend to exchange tiny particles called gravitons.

The gravitons must be exchanged in a very short time frame.

Question 34

What does geocentric mean?

Answer 34

The view that the earth is placed at the center of the solar system.

Question 35

What does heliocentric mean?

Answer 35

The view that the sun is placed at the center of the solar system.

Question 36

What astronomers supported the heliocentric point of view?

Answer 36

Copernicus, Galileo, Newton

Question 37

Kepler’s Laws

Answer 37

A series of rules that the planets always followed.

Question 38

What are the inner planets?

Answer 38

Mercury, Venus, Earth, Mars

Question 39

What are the outer planets?

Answer 39

Jupiter, Saturn, Uranus, Neptune

Question 40

If there is a moon that orbits a planet in 5 months and a second moon orbits a second planet in 12 months. They are the same distance from their planets. Which one has greater gravitational force imposed upon it?

Answer 40

The one that is moving faster (5 months). The principles of circular motion state that the faster the speed, the greater the centripetal force necessary.

Question 41

If a scientist determines that there are only 2 fundamental forces in nature (the electroweak force and the strong force), Which of the two current theories of gravity does he believe is true? and why?

Answer 41

The General Theory of Relativity, because this theory states that gravity is not actually a force.