Physics 1/2 (complete) Flashcards
1
Q
what is a scalar
A
has only magnitude
2
Q
what is a vector
A
has both magnitude and direction
3
Q
what are some scalar quantities
A
length, area, volume
speed
mass, density
pressure
temperature
energy, entropy
work, power
4
Q
what are some vector quantities
A
displacement
velocity
acceleration
momentum
force
lift, drag, thrust
weight
5
Q
what is the definition of force
A
any force (visible/invisible) capable of causing a mass to accelerate
6
Q
what is newtons first law of motion
A
lst = Interia
any object at rest will stay at rest, and an object in motion stays in motion, unless acted upon
7
Q
inertia
A
capability of an object to resist changes in velocity
8
Q
mass
A
measure of inertia
9
Q
center of mass
A
weighted average of the mass of an object
10
Q
what is newton’s second law
A
F=ma
a net force will increase velocity, but will maintain a constant acceleration
11
Q
what is newton’s third law
A
when object 1 exerts a force on object 2, object 2 exerts an equal, but opposite force on object 1
12
Q
what is velocity
A
speed
displacement over time
13
Q
what does constant velocity mean?
A
- no acceleration (no net force, all forces sum to 0, object is in equilibrium)
- no change in direction
14
Q
acceleration
A
change in velocity over time
15
Q
what is the formula for distance traveled
A
d=1/2*at^2
d=distance
a=acceleration
t=time
16
Q
what is the formula for velocity
A
v= square root of 2gh
v=velocity
g= acceleration due to gravity
h=distance
17
Q
time in air
A
tair= 2v/g
18
Q
when should air resistance be taken into consideration
A
only when the question says so
19
Q
when is air resistance increased
A
when there is an increase in surface area, larger shape, and increased velocity
20
Q
terminal velocity
A
point at which the forces due to gravity are matched by forces due to air resistance, resulting in no acceleration
21
Q
gravity
A
any invisible field resulting in an attractive force between objects that have mass
22
Q
constant field (near earth)
aka potential energy
A
PE=mgh
23
Q
point charge (far from earth)
A
PE= - (GM1M2)/r
24
Q
force due to gravity
A
F= (Gm1m2)/r^2
25
what is friction
nonconservative force occurring due to intermolecular interactions
prevents sliding
26
kinetic vs static friction
kinetic: object is accelerating
static: object is at rest
27
which coefficient is larger? static or kinetic
ALWAYS static
28
formula of density
d=m/V
29
general pressure equation
general pressure= force/area
30
pascal's law
pressure applied in on part of an incompressible fluid is transmitted undiminished in all direction
31
bernoulli's principle
pressure and velocity are inversely correlated
32
explain velocity and pressure in terms of window opening and air coming in
windows are down. at low velocities, there's not much air entering the car, but at the high velocities air rushes in like crazy. as velocity increases, the pressure in your car decreases, and air flows from high pressure outside to low pressure inside
33
what is hooke's law? what is another way to write it?
F=-kx
k= spring constant
x= distance spring is stretched
F=k*deltax
34
what is the specific gravity the ratio of
gravitational force and buoyant force
35
what is static object? (which forces are acting on the object)
no forces acting on the object, the object is at rest
36
what is the kinetic object? (what forces are acting on it)
no net force. object is moving, but not accelerating
37
what is torque
force applied at distance "I" from the point of rotation
38
what is energy
the capacity to do work
39
kinetic energy formula
1/2mv^2
40
what is the law of conservation of energy
energy in a closed, isolated system is always conserved
41
what is internal energy
energy dissipated as heat (SAME AS HEAT ENERGY)
42
what is heat energy
energy dissipated as heat (SAME AS INTERNAL ENERGY)
43
what is chemical energy
energy contained with chemical bonds
energy stored/released by the separation of electrons
44
what is mechanical energy
sum of kinetic and potential energy in a system
45
what are the 4 ways to think of work
1. work = change in energy
2. work = force applied over a distance
3. 1st law of thermodynamics: change in the energy of a system is due to either work or energy
4. work-energy theory: if work is done on an object, the work done is equal to the change in kinetic energy of the object
46
what is the purpose of a simple machine
to reduce the force needed to perform a given amount of work, but it DOES NOT decrease the amount of work needed
47
when thinking of power, what is the 4 ways to think about it?
1. P= change of energy/time
2. P=work/time
3. P= (force times dcostheta)/time
4.Pinstantaneous = force x velocity x costheta
48
when it comes to negative and positive change, how does it connect to the amount of electrons
negative: excess of electrons
positive: shortage of electrons
49
conductance promotes movement of? what do insulators inhibit?
the movement of electrons, insulators inhibit the movement of electrons
50
what is the electric field
invisible influence capable of exerting a force on a mass or charge
51
what is voltage
electrical potential energy caused by the separation of charge
potential energy per unit charge
52
what is a current? what is the charge?
current is the flow of POSITIVE charge
flows in opposite direction of electron flow
change in charge over time
53
what is the equation of resistance
R= (pL)/A
p=resistivity
L=length
A= cross-sectional area
54
what is Ohm's law
V=IR
R= constant (resistance)
V= voltage
I= current
55
magnetism is similar to what
electricity
56
what are magnetic fields created by
changing electric fields
57
what is the curl right hand rule
direction of magnetic field (the way the fingers fold in when you do thumbs up)
direction of current flow (the way the thumb goes - up)
58
what is fleming's right hand rule
thumb: direction of force
first finger: direction of field
middle finger: direction of current
(hand is held up with thumb facing up, first finger facing out, and middle finger facing inward at 90 degrees)
59
what are circuits? does it flow the same with electron flow?
think of current as the flow of positive change
- flows in the opposite direction of electron flow
60
what does the switch open __/ ___ and
close ____ mean
open: circuit is open and incomplete
closed: circuit is closed and complete
61
what is the equation for capacitors in parallel?
Ctotal = C1+C2+C3
think of a box with the capacitors in a straight vertical line
capacitors are the open ones
62
what is the equation for capacitors in series
1/Ctotal = 1/C1 + 1/C2 + 1/C3
thing of a box with the open capacitors in a horizontal straight line
capacitors are the open ones
63
what is the equation for resistors in series
Rtotal= R1+R2+R3
think of a box with resistors in straight horizontal line
resistors are the ones with squiggly lines
64
what is the equation for resistors in parallel?
1/Rtotal = 1/R1 + 1/R2 + 1/R3
think of a box with the resistors in a straight vertical line
resistors are the ones with squiggly lines
65
how to batteries in series differ from batteries in parallel?
think in terms of voltage, current and capacity
series: add voltage together, current and capacity stay the same
parallel: add current or capacity together, voltage stays the same
66
what is the equation of electrical power
power= current x voltage
P=IV
67
for sound/mechanical waves, how does intensity relate to amplitude and frequency
intensity is proportional to amplitude and frequency
68
for light waves, how does intensity relate to amplitude and frequency
intensity is ONLY proportional to amplitude
69
electromagnetic waves are
transverse waves capable of propagating without a medium, transfer energy and momentum
70
mechanical waves
require a medium to propagate, only transfer energy (not matter)
71
what is the wave speed equation
v=λf
v=speed/velocity
λ= wavelength
f= frequency
72
transverse waves
strings on a musical instrument
73
longitudinal waves
sound waves
74
3 wave rules
what is wave speed determined by?
does frequency change from medium to medium? how about wavelength
wave speed is determined by the medium
frequency NEVER changes from medium to medium
wavelength DOES change from medium to medium
75
what is a node on standing waves? how about antinodes
node: middle intersection from the wave
antinode: the not intersecting part
76
what is the doppler effect
the greater the relative velocity, the greater the shift in frequency or wavelength
77
higher pitch means (higher/lower) frequency
higher pitch = higher frequency
78
do vibrations travel through solids?
liquids?
gas?
solids and liquids - yes
they create pressure waves through gases
79
how is sound created
by a vibrating medium
80
light can exist as what two things?
particle and wave
81
what is the equation for energy of a photon
E=hf
h=planck's constant
f= frequency
82
what 'nm' is visible light
390-700
83
when looking at a wave, how do you see energy and wavelength
the tighter the waves, the decrease wavelength and increasing energy
the more spread out the waves, the increasing of the wavelength and the decreasing of energy
84
on the spectrum, how do rays/waves fit
gamma, xray, visible light, radio waves, IR, UV
least to largest
gamma
xray
UV
visible
IR
radio
85
what is snell's law
n= c/v
n= index of refraction of a medium
c= speed of light in vacuum
v= speed of light in the medium
86
virtual images are (upright/inverted) and (negative/positive)
virtual images are upright and negative
87
real images are (upright/inverted) and (negative/positive)
real images are inverted and positive
88
what is a converging lens and what is it used for
it is the fat lens
usually a positive, real, inverted image
89
what is a diverging lens and what is it used for
skinny lens
always negative, virtual, upright image
90
where is the image focused in nearsightedness
visual image is focused in front of retina
91
where is the image focused in farsightedness
visual image is focused behind the retina
92
normal vision interacts how with retina
normal vision occurs when light is focused directed on the retina rather than in front or behind
93
two lens system
the image of the first lens becomes the object for the second lens
94
photoelectric effect
When light shines on a metal, electrons can be ejected from the surface of the metal (bounces)
95
young's double slit
light is passed through two slits and forms an interference pattern on a screen behind the slits
96
what are the 2 formulas for frequency/wavelength?
from those 2 formulas, how can you get the formula for energy?
photon energy: E= hf (f=frequency, and h=constant: 6.626x10^-34)
frequency: f=c/l (c=light constant: 3x10^8), and l=length
this would mean: E= hc/l
97
potential energy formula
PE=mgh
98
what is the Venturi/Bernoulli's effect
speed of a liquid increases, the pressure drops
99
Buoyant force - definition and formula
upward force a fluid exerts on an object
F=pvg
p= density
v=volume
g=gravitational constant
100
what is the gravitational constant
9.8 m/s^2
101
when given an open container with liquid and closed container with liquid, which would have the higher pressure and why?
the open container
the open one would have absolute pressure (SUM OF GAUGE PRESSURE AND ABSOLUTE PRESSURE) while the closed container would only have gauge pressure
102
difference in the equation for frictional force vs normal force
frictional uses SIN (mgsin theta)
normal uses COS (mg cos theta)
