Physics of human affairs test 1

Question 1

Aristotle’s achievements

Answer 1

rules of formal logic
rules of writing drama
optics
taxonomy
anatomy

Question 2

Aristotle’s physics

Answer 2

formed off observations!
- if you drop a rock, it will fall
- a rock falls faster than a feather
- INCORRECTLY CONCLUDED that things fall according to their weight
-water rolls downhill
-flames leap upward
-sky exhibits repeatable patterns (day and night phases of the Moon seasons)
- if you push a cart and let go, it will come to a stop

Question 3

aristotles model of physics

Answer 3

linked w model of cosmology
divided everything into 5 elements
eath (solids)
water (liquid)
air (gas)
fire (heat)
aether (the sky)

Question 4

Natural motion

Answer 4

the five elements seek their own place in the universe

-eath seeks to move downward
-water seeks its place above earth
-air seeks its place above air
-fire seeks its place above air
-aether (celestial motion) mostion of the planets stars etc.

Question 5

violent motion

Answer 5

motion influenced by humans or animals

Question 6

Galileo

Answer 6

• 1610 regognized the weaknesses of Aristotle’s physics
• he saw the value in aristotle’s observation-based approach
• further developed aristotle’s methods into what we now call the scientific process

Question 7

galileo’s scientific process

Answer 7

studied motion using the following tools
- experiment or a controlled observation designed to test a specific hypothesis
-idealization or eliminating external influences. For example, minimizing friction as much as possible
-limiting the scope of inquiry to answer one question at a time
-quantitative methods. take measurements and do math

Question 8

Inertia

Answer 8

Hypothesis (aristotle) : a moving object eventually comes to a stop, due to its natural motion
Observation (Galileo): if you minimize friction a ball rolling on a flat surface will keep rolling
Aristotle’s hypothesis was contradicted
- Hypothesis (Galileo): a moving object has inertia or a tendency to keep moving

Question 9

Law of Inertia

Answer 9

an object in motion will stay in motion until an external force acts on it
(newton’s first law of motion)
i.e. friction

Question 10

Delta symbol

Answer 10

means “change in”

Question 11

t means

Answer 11

time
delta t means change in time

Question 12

x means

Answer 12

position
delta x means
change in position
straight-line distance between start and finish

Question 12

speed

Answer 12

a change in position over a very small time

delta x/ delta t

Question 12

units of speed

Answer 12

meters per second m/s
kilometers per second km/h
miles per hour mph

Question 12

velocity written out

Answer 12

60 km/h westbound

Question 12

vector

Answer 12

a quantity (like velocity) that includes a direction

Question 12

velocity

Answer 12

a speed and a direction

Question 13

acceleration

Answer 13

a change in velocity over time

deta v/ delta t

Question 14

units of acceleration

Answer 14

meters per second squared (m/s^2) feet per second squared (ft/s^2)

Question 15

Galileo also created…

Answer 15

The laboratory!

Question 16

acceleration is a vector meaning…

Answer 16

-it has direction
-to speed up is to accelerate forward
-to slow down is to accelerate backward

direction of motion and acceleration can be different

Question 17

what is an example of centripetal acceleration

Answer 17

to turn a corner is to accelerate inward, toward the center of the curve

Question 18

how to NOT accelerate

Answer 18

stay still
move in a straight line with constant speed

Question 19

freefall

Answer 19

falling with no influence except gravity

falling without air resistance

Question 20

Hypothesis of freefall (galileo)

Answer 20

objects in freefall accelerate downward as they fall

Question 21

Galileo’s freefall experiment

Answer 21

falling objects are hard to study because they move too fast

solution: slow them down

instead of dropping a ball, let it roll down a gentle slope

Question 22

galileo’s freefall analysis

Answer 22

as the slope gets steeper, the ball moves closer and closer to a state of freefall

Question 23

galileo’s law of falling

Answer 23

if air resistance is negligible, all objects fall in the same way

Question 24

general acceleration due to gravity

Answer 24

an object in freefall accelerates toward Earth at about 10 m/s2

Question 25

Newton’s Discoveries

Answer 25

Developed calculus
so did leibniz but they were rivals

Question 26

concepts for newtonian physics

Answer 26

velocity- a speed and direction
acceleration- a change in velocity. in other words, a change in speed or direction
mass- amount of matter in an object
force- push or pull

Question 27

principles for newtonian physics

Answer 27

law of inertia: an object in motion will stay in motion unless acted on by a force
- the law of inertia was discovered by galileo and further studied by newton
- sometimes called newtons 1st law
law of falling: all objects in freefall (wiht no air resistance) fall with the same acceleration
- the law of falling was discovered by galileo and further studied by newton

Question 28

principles discovered by newton

Answer 28

the law of motion (newtons 2nd law)
the law of force pairs (newtons 3rd law)
the law of gravity

Question 29

Force!!!

Answer 29

an influence that can cause an acceleration
they’re external!

Question 30

units of force

Answer 30

american : lbs
metric : Newton (N)
Newton is also a unit of weight

your weight is the force with which gravity pulls you

Question 31

net force

Answer 31

a force is an influence that can cause acceleration

a net force is an influence that does cause acceleration

it is an imbalance of forces acting on an object

Question 32

mass

Answer 32

mass is the amount of matter in an object

mass is like weight, except weight depends on gravity and mass does not

Question 33

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