Unit 3 Concept Cards

Question 0

3.2 Copernicus
Astronomer of the 1500’s who said the “universe” was heliocentric rather than geocentric.
Unit 3 Chapter. 2
Text book

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Answer 0

• in the early 16th century copernicus formed his theory of thee moving earth
• Copernicus stated the reason all other solar things move is because the earth orbits the sun
• for many years he kept his findings a secret due to fear of persecution for such a new theory he also kept his findings in the dark because of self doubt
• the first time he saw his findings in print was on his death bed

Question 1

3.1 Aristotle
Unit 3 Chapter 2
Aristotle was the most famous and revered philosopher and scientist of ancient Greece. (350 BC)
Text book

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Answer 1

Aristotle classified motion into two basic groups natural motion and violent motion

• natural motion comes from the nature of an object an example of this is that heavier objects fall faster than smaller objects do natural motion can either be up and down or circular like a celestial object
• violent motion is a result of forces like pushing and pulling it is an imposed motion an example off this is somebody pushing a lever forwards the main point of violent movement s things need other things to help them move so in other words they need an outside force to act upon then to move
• Aristotle believed that all motions are the result of an objects nature or a push/pull thAT provided an object is in its proper place it will not move without a force of some sort except for celestial objects since there normal state is one of rest

Question 2

3.3 Galileo
Galileo was a scientist of the 1600’s (renaissance) who used experiments to test ideas of motion and developed the concept of inertia.
Unit 3. Chapter 2
Textbook

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Answer 2

Galileo was a seventeenth century philosopher who easily disproved Aristotle’s falling objects hypothesis

• he was more concerned with how things move oppose to why
• Galileo focused on experiments rather than just pure logic he disagreed with aristotles ideas

Question 3

3.4 Newton
unit3 chapter 2
Newton was an English Scientist in the late 1600; early 1700’s whose 3 laws of motion laid the foundations for the science of physics.
Previous class

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Answer 3

Newtons 3 laws
First law: When viewed in an inertial reference frame, an object either remains at rest or continues to move at a constant velocity, unless acted upon by an external force.(law of inertia)

Second law: For every action, there is an equal and opposite reaction.

Third law: When one body exerts a force on a second body, the second body simultaneously exerts a force equal in magnitude and opposite in direction on the first body.

Question 4

3.5 Inertia
unit 3 chapter 2
Newton’s first law of motion states that every object continues in a state of rest, or of uniform speed in a straight line, unless acted on by a nonzero force.
KA and Textbook

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Answer 4

Inertia is the resistance of any physical object to any change in its state of motion, including changes to its speed and direction. It is the tendency of objects to keep moving in a straight line at constant velocity.

Question 5

3.6 Force:
unit 3 chapter 2
A force is needed to change an object’s state of motion.
KA

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Answer 5

a force is simply a push or pull
Forces include spring force(Fs),applied force (Fa),weight( Fw or Fg),tension (Ft),Support force(Fn),friction force (Ff) and air resistance (Fair

Question 6

3.7 Mechanical Equilibrium:
unit 2 chapter3
Mechanical Equilibrium exists when the sum of the forces on an object = O.
KA and class

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Answer 6

A mechanical equilibrium is a state in which a momentum coordinate of a particle, rigid body, or dynamical system is conserved. Usually this refers to linear momentum.2 types static and dynamic

Question 7

3.8 Support Force:
unit 3 chapter 2
The support force is an upward force balancing the downward force of gravity on an object.
Book

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Answer 7

• upward support force : also called normal force it is equal and opposite of the force it is acting on it so for downward upwards
• Gravitational force: the force of gravity acting on you

Question 8

3.9 Vectors:
Unit 3 chapter 2
Vectors are used to represent quantities that have magnitude AND direction.
Textbook and class 
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Answer 8

are represented by arrows that represent force they are added and you can calculate them with the Pythagorean theorem

Question 9

3.10: Vectors at right angles:
Unit 3 chapter 2
When vectors are at right angles to each other the Pythagorean theorem can be used to determine the resultant.

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Answer 9

pytheorean theorem: A2+B2=C2

use this to find magnitude of results

Question 10

3.11 The Parallelogram rule
The Parallelogram rule is used to find the resultant of any two vectors at any angle (other than 0 or 180 degrees)
Book and KA

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Answer 10

Use Pythagorean theory to solve

Question 11

3.12 Freebody diagrams
Unit 3 chapter 2
Freebody diagrams show all of the forces acting on one object.
KA

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Answer 11

Free body diagrams are used to represent the force acting on object they are. Made up of arrows and a box

Question 12

3.14 Mass
Unit 3 chapter 2
Mass is how much matter is in an object and it is a measure of inertia
Class Discussion

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Answer 12

Mass ifs the force of gravity pulling on your weight