Science Final Flashcards
(134 cards)
1
Q
Acceleration
A
how speed changes over a period of time
2
Q
Average speed / speed
A
total distance covered divided by total time taken to cover that distance
3
Q
constant speed
A
speed that remains the same over a particular time period
4
Q
instantaneous speed
A
speed at a particular moment
5
Q
velocity
A
change in speed over a period of time that also involved some type of direction (mph north)
6
Q
inertia
A
an objects ability to resist change in a state of motion
7
Q
Law of Conservation of Momentum
A
states that momentum is always conserved in any interaction
8
Q
Newtons First Law of Motion
1st LOM
A
an object at rest stays at rest, and an object stays in motion, Unless acted upon by an unbalanced, outside force
9
Q
Newtons Second Law of Motion
2nd LOM
A
force = mass * acceleration (f=m*a)
10
Q
Newtons Third Law of Motion
3rd LOM
A
for every action there is an equal and opposite reaction
11
Q
Unbalanced forces
A
forces that cause acceleration
12
Q
efficiency
A
the ratio of output work divided by input work, a percentage, nothing is ever 100% efficient
13
Q
energy
A
the ability to do work
14
Q
energy transfermation
A
energy changing from one form to another
15
Q
heat
A
thermal energy that is moving or capable of moving
16
Q
horsepower
A
unit of power
= to 746 watts
17
Q
Joule
A
equal to 1 newton times 1 meter, unit of energy and work
18
Q
kinetic energy
A
energy of motion
19
Q
Law of conservation of energy
A
energy cannot be created or destroyed, only transferred
20
Q
potential energy
A
energy that is stored, comes from position
21
Q
gravity (g) on earth
A
g=9.8
22
Q
power
A
the rate of doing work
23
Q
watt
A
unit of power
24
Q
work
A
force times distance or power times time, but the force applied must be in the same direction as the distance it moves
25
examples of work
lifting, pushing, pulling
| NOT carrying or losing tug of war
26
atomic mass
protons + neutrons
27
electrons
equal to number of protons, negative charge, outside nucleus, have levels
28
groups
down (columns) on periodic table, valence electrons
29
isotopes
same element, different mass number
30
mass number
number of protons (or electrons)
31
metal
takes up most of the elements on the table, left side
32
neutron
in nucleus, neutral
33
noble gasses
column 18, full balanced shell (8), don't react (except helium)
34
nonmetal
takes up right side of table
35
nucleus
99% of mass in an atom, made up of protons and neutrons
36
period
across (rows) on periodic table, energy level
37
periodic table
a table you use periodically (jk)
38
proton
positive charge, in nucleus
39
Chemical bond
the joining of atoms to form new
40
covalent bond
bond between two nonmetals , electrons are shared, (greek prefixes)
example: H2O
41
Ion
term used to describe an atom with a charge other then zero
42
ionic bond
bond between metal and nonmetal, electrons are transferred, (-ide) (no prefixes)
example: MgBr2
43
Lewis Dot Diagram
method used to visually represent valence electrons
44
Oxidation number
represents how many electrons to give or take to get full outer shell, and/or what the most likely charge on an atom will be (electrons are lost, gained or shared)
45
valence electrons
number of electrons in outer shell, determine how atoms react, involved in chemical bonding
46
addition (synthesis) reaction
2 elements combine to make a compound
| example: 2Na+Cl2-->2NaCl
47
chemical change
a change that results in a new substance being formed
48
chemical equation
short hand way to show chemical reaction
| example: H2+O2-->H2O
49
coefficient
number put in front of a chemical formula to balance it
| examples in chapter 17 packet
50
combustion reaction
reaction in which CO2 + H2O + energy is produced
51
decomposition reaction
a compound breaking down into 2 or more elements
| example: H2CO3-->H2O+CO2
52
double displacement (replacment) reaction
an element in 2 different compounds switch places
| example: NaCl + AgF --> NaF + AgCl
53
formula mass
found by combining the individual mass of each atom in a compound
54
physical change
a change that does not result in a new substance being formed
55
product
what is formed in chemical reaction, right side of arrow
56
reactant
what takes part in chemical reaction, left side of arrow
57
single displacement replacment) reaction
an element replaces another element in compound
| example: Zn +2HCl --> ZnCl2 + H2
58
fulcrum
| Glodek said this is 10/10 important
stiff structure that separates the input force and output force (needed for all levers)
59
gears
rotating wheel with teeth that transfers motion forces to other gears or objects
60
input
force energy or power supplied to make a machine accomplish a task
61
input arm
side of lever in which input force is applied
62
input force
force that is applied to a machine
63
lever
stiff structure that rotates around a fixed point (3 classes of levers
64
1st class lever
fulcrum is right in the middle of output and input (OFI), output force is equal to input force (O=I) , ex: a see-saw
65
2nd class lever
fulcrum then output then input (FOI), output force is greater then input force (O>I), ex: a wheelbarrow or door
66
3rd class lever
fulcrum then input then output (FIO), output force is less then input force (I>O), ex: your arm, jaw, or a broom
67
machine
a devise with moving parts that work together to complete a task
68
```
mechanical advantage
(Glodek said this is very very important)
```
ratio of output force divided by input force (O/I)
69
output
forces energy or power provided by machine
70
output force
force that is produced by a machine
71
pulley
a simple machine that can increase force by changing direction
72
simple machine
unpowered mechanical device that accomplishes a task with 1 step or motion
73
amplitude
the amount that a cycle moves away from equilibrium
74
cycle
one repetition of motion
75
frequency
how often something repeats, expressed in hertz
76
harmonic motion
motion that repeats in cycles
77
hertz
unit of frequency, 1 hertz = 1 cycle per second
78
linear motion
motion that goes from one place to another without repeating
79
natural motion
the frequency at which a system vibrates when it is disturbed
80
oscillator
physical system that has repeating cycles
81
period
the time it takes to complete one cycle
82
periodic force
repetitive force
83
resonance
an exceptionally large amplitude that develops when a periodic force is applied to a natural frequency
84
restoring force
force that acts to pull a system back to equilibrium
85
wavelength
distance from crest to crest to trough to trough of any wave
86
Acceleration formula
(final speed - starting speed)/ time
87
Speed and velocity formula
speed=distance/time
88
momentum formula
mass * velocity
89
force formula
force = mass * acceleration (f=m*a)
90
efficiency formula
work output /work input (will equal a decimal)
91
kinetic energy formula
(1/2) mass * velocity squared
| Ek=(m*v^2)/2
92
potential energy formula
mass* gravity (9.8)*height
| Ep= mgh
93
work formula
force*distance (w=f*d)
| power*time (w=p*t)
94
mechanical advantage formula
output force/ input force
95
mechanical advantage of a lever when given the arms formula
input arm /output arm
96
density
mass/volume
97
dependent variable
what is measured from experiment, plotted on Y axis
98
direct relationship
increase in 1 variable and produces same increase in another variable
99
gram
metric unit of mass
100
graph
shows how variables relate
101
independent variables
the one variable that is changes in experiment, plotted on X axis
102
inverse relationship
increase in 1 variable produces decrease in another variable
103
kilogram
=1,000 grams, basic unit of mass in metric system
104
mass
amount of matter
105
scatterplot
graph that shows relationship between 2 variables
106
volume
amount of space an object takes up
107
weight
depends on mass and gravity, Not the same as mass
108
Kinetic energy increases with:
mass and speed.
109
Efficiency is defined as the ratio of:
work output to work input.
110
When constructing a graph, the x-axis is most closely related to:
the independent variable.
111
The "building blocks" of matter are:
atoms and molecules.
112
The inertia of an object is related to its:
mass only.
113
The second row of the periodic table has 8 elements because:
the second energy level can hold 8 electrons.
114
If you go twice as fast, your kinetic energy becomes:
4 times bigger.
115
Batteries are devices that change chemical energy to ____ energy.
electrical
116
The rate at which velocity changes is called:
acceleration.
117
The density of a liquid is higher than the density of a gas because:
particles of a liquid are closer together than particles of a gas.
118
Newton’s first law of motion is also known as:
the law of inertia.
119
The variable usually represented on the x-axis is the ____ variable.
independent
120
A scatterplot is the best type of graph to use when:
one variable causes a second variable to change in value.
121
In order for evidence to be considered scientific evidence, it must be:
objective and repeatable.
122
Compared to protons, electrons have:
much smaller mass and opposite charge.
123
Atomic number is:
the number of particles in an atom.
124
what are the horizontal rows on the periodic table called?
periods
125
what are the vertical rows on the periodic table called
groups or families
126
A unit used to measure the period of a cycle is the:
second.
127
An object at rest has:
inertia but no momentum.
128
If the mechanical advantage of a simple machine is 5, then:
the output force is 5 times greater than the input force.
129
A longitudinal wave travels:
in the same direction as the oscillations.
130
The amount of time required for one cycle to occur is called the:
period.
131
Which of the following use the same units of measurement?
Energy and work
132
Kinetic energy increases with:
mass and speed
133
energy can be considered stored:
work
134
simple machine can multiply
force and speed
