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Physics Flashcards

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1
Q

Nano (n) stands for

A

10-9

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2
Q

Pico (p) stands for

A

10-12

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3
Q

Micro (u) stands for

A

10-6

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4
Q

milli (m) stands for

A

10-3

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5
Q

centi (c) stands for

A

10-2

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6
Q

kilo (k) stands for

A

103

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7
Q

mega (M) stands for

A

106

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8
Q

giga (G) stands for

A

109

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9
Q

Name the five equations from “The Big Five” in regards to uniform acceleration?

A
  1. d = 1/2(V0+V)t
  2. V = V0 +at

d = V0t + 1/2at2

d = Vt - 1/2at2

V2=V02 + 2ad

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10
Q

What is gravity’s acceleration?

A

10m/s2

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11
Q

Formula for weight

A

w=mg

w= weight

g= gravity acceleration

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12
Q

What is the formula for Newton’s Law of Gravitation?

A

Fgrav= G (Mm)/(r2)

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13
Q

what is the formula for finding gravitational acceleration, g?

A

g = G (M/r2)

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14
Q

What is formula for velocity (V)?

A

V = d/t

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15
Q

What is formula for acceleration (a)?

A

a = V/t

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16
Q

What is Newton’s first law?

A

An object at rest will stay at rest, an object in motion will stay in motion

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17
Q

What is Newton’s second law?

A

F=ma

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18
Q

What is Newton’s third law?

A

For every action, there is an equal and opposite reaction

F1 on 2 = -F2 on 1

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19
Q

Friction Force = ?

A

Ff = µkFN

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20
Q

Friction force max =?

A

Ffmax= µsFN

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21
Q

Force parallel to inclined plane =?

A

mgsinΘ

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22
Q

Force perpendicular to inclined plane = ?

A

mgcosΘ

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23
Q

What is the equation for finding the center of mass for point masses?

A

Xcm = m1x1 + m2x2…./m1 + m2…

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24
Q

What is the equation for finding the center of gravity?

A

Xcg = w1x1 + w2x2…../w1 + w2…

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25
Q

acceleration of uniform circular motion =?

A

ac=v2/r

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26
Q

What is the formula for finding force of circular motion?

A

Fc=mac=mv2/r

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27
Q

Ƭ, torque =?

A

Ƭ = rFsinΘ

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28
Q

Define torque

A

torque is a measure of a force’s effectivness at making an object spin or rotate (accelerate rotationally)

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29
Q

What is rotational inertia?

A

Resistance to rotational acceleration

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30
Q

Which is easier to rotate: Weights very close together at the center of mass, or weights very far apart?

A

Close together

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31
Q

F=ma, how does this apply to torque and inertia?

A

Ƭnet= Iα

I is rotational inertia

alpha is rotational acceleration

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32
Q

Describe how the rotational axis affects the rotational inertia

A

The inertia will be smallest when the rotation axis passes through the objects center of mass

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33
Q

Which has smaller rotational inertia: solid ball or hollow ball

A

Solid ball - therefore it would roll more easily than the hollow ball

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34
Q

W (work) =?

A

W=Fd

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35
Q

P (power)=?

A

P = W/t

work/time

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36
Q

KE=?

A

1/2mV2

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37
Q

Total work =?

A

change in KE

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38
Q

PE=

A

mgh (if height increases)
-mgh (if height decreases)

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39
Q

E=

A

E= KE + PE

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40
Q

Conservation of total mechanical E equation

A

KE + PE = KE2 + PE2

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41
Q

What happens to PE and KE when there is friction?

A

total mechanical E is not conserved.
KE + PE + Wby F= KE2 + PE2

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42
Q

MA (mechanical advantage) =

A

MA = deffort/dresistance

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43
Q

Describe the difference in lifint a block 2 m and pushing it up a ramp 2m in height

A

The ramp takes less force but the work ends up being the same

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44
Q

Efficiency =?

A

Woutput/Einput

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45
Q

What is unit for F

A

N

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46
Q

What is unit for W?

A

J

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47
Q

What are the three ways energy can be transferred? Describe

A

Conduction - direct transfer of E (touching the hot stove)

Convection - E transferred like a fluid (candle warming air)

Radiation - Absorption of E via light waves (sun warming)

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48
Q

What is symbol for momentum?

A

p

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49
Q

What is unit for momentum? (p)

A

kg • m/s

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50
Q

Is momentum a vector?

A

Yes - it includes direction!

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51
Q

p=

A

p=mv

(momentum)

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52
Q

What is symbol for impulse?

A

J

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53
Q

What is unit for impulse? (J)

A

N • s

(second)

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54
Q

J=?

A

Δp=Δmv=FΔt

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55
Q

Momentum is conserved within a system. What equation describes this?

A

m1V1 + m2V2 = m1V1’+ m2V2’

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56
Q

What are the three kinds of collisions? Describe them

A
  1. elastic - total momental & total KE conserved
  2. Inelastic - total momentum conserved NOT total KE
  3. Perfectly inelastic: obejcts stick together afterwards. momentum is conserved.

Elastic collision is the only one KE is conserved in

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57
Q

Ball 1 and Ball 2 roll toward each other at the same speed, 5 m/s. Ball 1 = 8kg, Ball 2=2 kg. After collision, they stick together. What is new velocity after collision?

A

3 m/s

8kg * 5m/s + 2kg * -5 m/s = 10kg *?

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58
Q

What is the symbol for angular momentum?

A

L

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59
Q

Angular momentum (L) =?

A

L = lmv = Iw

(el)mv (eye)w

Just multiply linear momentum by length (p=mv)

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60
Q

The greater the change in momentum, the _____________ the impulse required

A

greater

J = Δp

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61
Q

Angular momentum =?

A

L=lmv = Iw

l (el) is lever arm, m is mass, v is velocity

I(eye) is moment of inertia, w is angular velocity

L is angular momentum

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62
Q

What is law of conservation of angular momentum?

Formula?

A

If net torque is 0, then total angular momentum doesn’t change

Li=Lf

Iiwi=Ifwf

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63
Q

What happens to moment of inertia and angular velocity when a sprinning ice skater pulls her arms closer to her body?

A

She pulls her arms closer to the axis of rotation, so her moment of inertia decreases and her angular velocity increases (she spins faster)

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64
Q

What is symbol for density?

A

p (but the p has a tail)

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65
Q

What is units for density?

A

kg/m3 or g/cm3

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66
Q

p (density) = ?

A

m/V

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67
Q

What is the density of liquid water?

A

1000 kg/m3 or 1 g/cm3

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68
Q

What is specific gravity? Formula?

A

How dense something is compared to water

Specific gravity = p/ph2o

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69
Q

If a graph plots position versus time, what does the slope =?

A

velocity

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70
Q

If a graph plots velocity vs. time, what does the slope =?

A

acceleration

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71
Q

What does the area under a graph = when plotting velocity vs. time?

A

d

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72
Q

A newton (N) =?

A

kg•m/s2

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73
Q

torque =?

A

(I)(alpha)

torque = rotational inertia * rotational acceleration

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74
Q

The farther awa the mass is from the axis of rotation, the _____ rotational inertia will be

A

greater

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75
Q

Does having a great amount of inertia mean it is difficult to rotate or easy to rotate?

A

difficult

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76
Q

Is rotational inertia greater when it passes through the objects center of mass or through its side?

A

Side, inertia is smallest when passing through center of mass

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77
Q

torque =? (in relation to r and F)

A

torque = rFsinØ

if torque is perpendicular to r, then torque=rf

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78
Q

Which rolls more easily? Solid ball or hollow ball? why?

A

Solid ball, because it has smaller rotational inertia, the rotation axis passes through the center of mass

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79
Q

Is work a vector or scalar?

A

scalar, it has no direction

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80
Q

What is the unit for work?

A

J (Joule)

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81
Q

1 J (joule) =?

A

N*m

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82
Q

W=?

A

W=Fd

(force * distance)

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83
Q

What is the definition of power?

A

How fast work gets done

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84
Q

1 watt=?

A

1J/s

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85
Q

Power (P)=?

A

P = W/t

work/time

P=Fv

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86
Q

KE=?

A

1/2mv2

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87
Q

Total mechanical E =?

A

KE + PE

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88
Q

equation for conservation of mechanical energy:

A

KE + PE = KEf + PEf

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89
Q

unit of momentum (p)

A

kg*m/s

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90
Q

is momentum a vector or scalar?

A

vector

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91
Q

p(momentum)=?

A

p=mv

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92
Q

J respresents what?

A

Impulse

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93
Q

J=?

A

J=►p=►mv=F►t

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94
Q

Law of Conservation of Total Angular Momentum

A

Li=Lf = Iiwi = Ifwf

(initial momentum = final momentum)

(Initial rotational inetial * initial angular velocity = finals)

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95
Q

is pressure a vector or scalar?

A

scalar

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96
Q

FB=?

(buoyant force)

A

FB=pVg

(density*volume that’s submerged*gravity)

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97
Q

Pascal’s Law formula

A

F1/A1=F2/A2

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98
Q

What is the surface tension of water?

A

.7 N/m

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99
Q

flow rate (fluid) =?

A

f=Av

area*velocity

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100
Q

A1V1=?

A

A2V2

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101
Q

Bernoullis equation? (ideal fluid)

A

P1 + 1/2pv12 + pgy1= P2 + 1/2pv22 + pgy2

p is density of flowing fluid

v is velocity

y is height above horizoantl reference

P is pressure

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102
Q

How fast does a liquid exit a hole? (equation)

A

Vefflux= Í2gD

(square root of )

D = y1-y2

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103
Q

Stress=? (opposed to pressure)

A

F/A

force/area

(the difference between pressure is pressure must be perpendicular to the object it acts on)

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104
Q

tensile or compressive strain =?

A

►L/L0

tensile/ compressive strain is stretching or squeezing

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105
Q

Shear Strain =?

A

x/L0

shear strain is bending

x=distance of shear/bend

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106
Q

Hooke’s law?

A

stress = modulus x strain

(modulus is a constant)

F=kX

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107
Q

Young’s modulus?

A

tensile and compressive stress

►L = FL0/EA

(FLEA!)
(E is modulus, unit is pascal)

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108
Q

The lower the modulus the ______ it stretches

A

more

109
Q

Shear modulus =?

A

(bending!)

X= FL0/AG

(FLAG!!)

G is modulus

110
Q

elementary charge =?

A

electric charge of proton or neutron

1.6 x10-19 C

111
Q

Formula stating that electric charge is always conserved?

A

q = n(+- e)

112
Q

What is avagadro’s number?

A

6.02*1023

113
Q

FE=?

(electric force)

A

k q1+q2/r2

k is proportionality constant, usually = 9*109 N*m2/C2

114
Q

Electric field vectors point _____ positive source charge and _______ negative source charge

A

away

toward

115
Q

EbyQ = ?

(electric field energy)

A

k Q/r2

116
Q

Fon q =?

A

F = qE

q is the charge that feels the field

E is in N/C

117
Q

Ø =?

(electric potential)

A

V = k Q/r

Ø unit is volt!!

118
Q

for electric potential:

►KE = -►PE

Postive charge (proton) increase KE when they move toward point of ____________

A

lower Potential

119
Q

negative charge ( electron) increase KE when they move toward point of ______________

A

higher potential

120
Q

Define current

A

net movement of charge

121
Q

I =?

(I is current)

A

I = Q/t

units of current is c/s

122
Q

A (ampere) =?

A

c/s

123
Q

R=?

(R is resistance)

A

R= V/I = p L/A

(voltange/resulting current)

p is resistivity which is intrinsic resistance

L is length

A is cross sectional area

124
Q

What is the unit of resistance?

A

ohms

125
Q
A
126
Q

Resistors in series

in parallel?

A

series: R = R1 + R2..
parallel: R1R2/R1 + R2

127
Q

What are capacitors?

A

Pair of conductors that can hold equal but opposite charge

128
Q

Q=?

(Charge on a capacitor)

A

Q=CV

C is a constant, capacitance, unit F ( farad)

129
Q

What does capacitance measure?

A

the “capacity” for holding charge

130
Q

PE=?

electrical PE stored in capacitor

A

PE = 1/2 QV

Q is charge on the capacitor

V is voltage

131
Q

Resistors in series always ahve the same ______, resistors in parallel always have the same __________

A

current (I)

voltage

((in a book series, the main character (I) is the same)

132
Q

P =?

power dissipated by the resistor (resistor gets hot!)

A

P=I2R

133
Q

P=?

Power supplied to the batter

A

P=IV

134
Q

What is the name of the thing that increases capacitance?

A

Dialetric, it is insulating material

135
Q

If a charge moves parallel to magnetic field lines ____

A

it feels no force

136
Q

FB=?

(magnetic force)

A

FB= q (v * B)

v is velocity of charge q

B is magnetic fieldc

137
Q

sin90=?

A

1

138
Q

a coil of wire is called a ?

What is inside of it?

A

solenoid

a magnetic field, parallel to central axis

139
Q

What is Hooke’s Law for Springs?

A

F = -kx

F is force exerted by spring

k is constant. the greater it is, the stiffer the spring

x is string’s displacement

140
Q

T respresent?

A

period, time it takes to complete one cycle (spring)

141
Q

f =?

Frequency

A

f = 1/T

T is period ( in seconds)

142
Q

*******

v =?

Wave speed

A

v = wavelength * frequency

f is constant - see big rules. wave speed is dependent on wavelength

MCAT LOVES WAVES

143
Q

What is Big Rule #1 for waves?

*********

A

The speed of a wave is determined by the type of wave and the characteristics of the medium NOT by the frequency

144
Q

What is Big Rule #2 for waves?

*******

A

When a wave passes into another medium, its speed changes but its frequency does not

145
Q

What does amplitude mean for waves?

A

How much E the wave transports. It has nothing to do with anything else

146
Q

Distance between two nodes (L) =?

A

1/2wavelength

147
Q

What does sound travel fastest through? Slowest?

A

Fastest through solids, then liquids, then gases

148
Q

What is intensity? (sound waves)

A

energy the sound wave transmits per second (power) per unit second, it is w/m2

w is watt

149
Q

What is intensity level?

A

The sound level.

150
Q

The Doppler Effect equation

A

fD=fs v+-vD/v-+vs

fD is frequency heard by detector

fs is frequency emitted by source

v is speed of wave

vd is speed the detector is moving

vs is speed source is moving

151
Q

f =?

focal length

A

f = 1/2 r

152
Q

what is the mirror and lens equation?

A

1/o + 1/i = 1/f

o is object’s distance from the mirror (ALWAYS positive)

i is image’s distance from the mirror

f is focal length of mirror

153
Q

with mirror and lenses, if both f and i are positive, then image is _____

A

on the same side as the human observer (but in lens oppostie sides)

154
Q

with mirror, if i is positive, image is ____

if i is negative, image behind mirror is _____

A

real

virtual

155
Q

m =?

m is magnification factor

if m is positive _____

if m is negative ______

A

m = -i/o

m + then image is upright

m - then image is inverted

156
Q

P =?

lens power

A

P = 1/f

f is focal length in meters

power unit is diopeter

157
Q

hyperopia is

A

farsightedness (can’t focus near)

158
Q

what lens is used to correct myopia?

A

diverging

159
Q

myopia is

A

near sightedness (can’t focus far away)

160
Q

what lens is used to correct hyperopia?

A

converging

161
Q

When a ball in projectile motion is launched, it does not accelerate: horizontally or vertically?

A

horizontally

162
Q

Velocity is the same at every point in projectile motion, once the ball is launched, for?

A

horizontal

163
Q

Equation for displacement for horizontal motion

A

x=v0t

164
Q

Equation for velocity for horizontal motion

A

vx=vox

165
Q

equation for acceleration for horizontal motion

A

ax=0

166
Q

Name equation for displacement for vertical motion

A

y=v0t + 1/2(-g)t2

167
Q

name equation for velocity for verticle motion

A

vy=v0y + (-g)t

168
Q

name equation for acceleration for verticle motion

A

ay=-g

169
Q

Newton’s law of gravitation equation

A

Fgrav=G Mm/r2

170
Q

according to newton’s law of gravitation: the magnitude of gravitational force is ______ proportional to the square of the distance b/w the centers of the object

A

inversely

171
Q

What will happen to the gravitational F b/w two objects if the distance between them is doubled?

A

Fgrav=G Mm/r2

If distances is doubled, then r increases by factor of 2, and Fgrav will decrease by factor of 22 = 4

172
Q

What will happen to the gravitational force between 2 objects if the distance is cut in half?

A

If distance is cut in half, then r decreases by factor of 2 and Fgrav wil increase by factor of 22 = 4.

Fgrav=G Mm/r2

173
Q

equation for gravitational acceleration?

A

g=GM/r2

g depends on radius and mass

M is mass

r is radius

G is universal constant

174
Q

Compare and contrast coefficient of kinetic friction (uk) vs coefficient of static friction (us)

A

Kinetic:

experimentaly determined

+ number with no units

the greater the number, the greater the force of kinetic friction

Static:

There’s a max between 2 surfaces

it is always larger than coefficient of kinetic friction

can only compute its max force (Ffmax=usFN)

175
Q

Draw an example force diagram with F parallel F perpendicular, FN, Ff

of a block sliding down a ramp

A
176
Q

A block of mass m=4kg is placed at the top of a frictionless ramp of incline 30 degrees and length 10m. What is the block’s a down the ramp? How long will it take for the block to slide to the bottom?

A

a = 5m/s2

t=2s

See green star page for how to calculate

177
Q

A block of mass m slides down a ramp of incline angle 60 degrees. If the coefficient of kinetic friction b/w the block and surface of the ramp is .2, what is the blocks acceleration down the ramp?

A

7.5m/s2

See green star page for how to do

178
Q

what is the formula for uniform (centripetal) acceleration?

A

ac= v2/r

179
Q

Torquenet=?

A

Ia

I = rotational inertia

a = rotational acceleration

Like F=ma! I is like mass, a is accerleration

180
Q

Define gravitational local, spring, and gravitational genearl PE (the equations)

A

a. gravitational, local (PE = mgh)
b. spring (PE = kx2
/2)
c. gravitational, general (PE = –GmM/r)

181
Q

In regards to torque, if it is spining counterclockwise it is____ vs. if it is spinning clockwise (positive or negative)

A

if CCW +

if CW -

182
Q

If torque a force?

A

No, it is a property of a force, it is a mesasure of the effectivness of a force at making an object spin or rotate.

183
Q

Is speed constant in uniform circular motion? is velocity constant?

A

Yes, speed is constant. But, velocity is a vector - so it keeps changing b/c it is going in a circle, therefore it is undergoing acceleration

184
Q

If a force acts at the pivot or along a lilne through th epivot, then it’s torque =?

A

0

185
Q

if we are given lever arm and force, how do they relate to torque?

A

torque = lF

(lever arm and force)

186
Q

contrast translational and rotational equilibrium

A

translational - forces cancel (Fnet = 0)

rotational - torques cancel (torquenet= 0)

187
Q

Work done by kinetic friction depends on ______

A

path taken (in contrast to “normal work” where direction doesnt matter, as its scalar

188
Q

What are the properties of an ideal fluid?

A

incompressible, neglible viscosity (syrup is very viscous), flow is laminar (aka flows smoothly), flow rate is steady

189
Q

Is the modulus for glass or rubber greater?

A

modulus is greater for glass - the lower the modulus the more it stretches

190
Q

If FE is positive, particles _______

A

repel each other

191
Q

If FE is negative, particles ______

A

attract each other

192
Q

If E (electric field) is positive, then Q is? If E is negative, then Q is?

A

E+ then Q+

E- then Q-

193
Q

Electric field diagrams indicate the direction of the electric force that a ______ would feel if it were placed in the field

A

positve test charge

194
Q

What is an electric dipole?

A

pair of equal but opposite charges

195
Q

In electric potential, we think of the electrif field as a ? (vector or scalar)

A

scalar - no direction. This helps us understand it in relation to energy, work, and speed.

196
Q

What is the unit for current (I) ?

A

c/s or A (amp)

197
Q

What causes current?

A

voltage

198
Q

What is voltage?

A

a potential difference

199
Q

voltages that create currents are called?

A

emf (electromotive force)

200
Q

What are the properties and formula of Ohm’s Law?

A

V=IR

Resistance is constant, voltage is varried, current reverses direction if polarity of voltage is reversed

201
Q

Draw a DC circuit

A

Direcrion direcion of current is toward negative terminal. It is the direction positive charge carriers would flow (even though what is actually happening is electrons are drifing towards higher potential (+)

202
Q

If there are three light bulbs in parallel and the middle burns out, what happens to the intensity, current, and power?

A

intensity of the other two stays the same. total current decreases. power supplied by battery will decrease. battery will last longer

203
Q

C = ?

C is capacitance

A

C = E0 A/d

Eo is fundamental constant of nature, permittivity of free space =8.85x 10-12 F/m

This measures the capacitator’s plates capacity of holding charge at a certain voltage

204
Q

Why use a capacitor?

A

To create a uniform electric field, and to store electircal PE

205
Q

Ed’s formula

A

V=Ed

explains that electric field b/w capacitance plates is same at every point

E is electric field

206
Q

C =?

in the presence of a dialectric

(capacitance)

A

C=KE0 A/d

K is dialectric constant. In a vacuum, this =1.

207
Q

If a dielectric is placed between a disconnected & charged capacitor, what happens to Q, C, V, PE, and E?

A

Q remains the same - charge cannot change if not connected to battery.

C increases - therefore V decreases (Q=CV)

E (electric field) decreases (V=Ed

PE decreases by factor of K (PE = 1/2QV)

208
Q

If dielectric is inserted while connected to the battery, what happens to C, Q, V, E and PE?

A

E-Einduced = E/K

Remember, K is dialectric constant

C=KE0 A/d

C increases by factor of K

Q increases by factor of K

V stays the same

E stays the same (V=ED)

PE increases by factor of K (PE = 1/2 QV)

209
Q

What is E induced in relation to dielectrics?

A

Dielectric polarizes molecules, creating induced charge on surface of the plates, creating a new electric field (E induced) in the opposite direction of the dielectric, leads to a decreaes in total electric field

210
Q

Draw and describe DC vs AC circuit

A
211
Q

Vrms=?

A

rms is root mean square, means average.

Vmax/ς2

(Vrms equals max voltage over square root of two)

212
Q

Irms=?

A

Imax/ς2

max current over square root of two

213
Q

What is a magnetic field created by?

A

Moving electric charges

214
Q

A magnetic field exerts a force on ______ but not on ________

A

exerts force on charge that is moving through the field, but not on a charge at rest

215
Q
  • vs. x
A

out of the page into the page

216
Q

Can magnetic forces do work?

A

NO. KE is constant. they cannot change speed of a particle, only direction of a particle.

217
Q

Explain L.H and R.H rule

A

if q is positive use RH

if q is negative, use LF

Thumb points i direction of velocity, fingers in direction of B. direction of FB will be perpendicular to palm

218
Q

If current is counterclockwise, B points _________ inside the loop and _______ outside the loop

A

out of the page inside the loop and into the page outside the loop

219
Q

If current is clockwise, B points ______ inside the loop and ____ outside the loop

A

into the page inside the loop and out of the page outisde the loop

220
Q

If solenoid has many windings and the length is much greater than the diameter, then the magnetic field is?

A

Almost uniform and is proportional the current and to the number of turns per unit length (N/L)

221
Q

Draw example magnet diagram

A
222
Q

In Hooke’s Law, the greter K is, the ______ the spring is

A

The greater K is, the stronger the spring is

223
Q

What is restoring force?

A

The force the spring provides because it is always trying to get back to equilibrium

224
Q

What is the unit for frequency?

A

Hertz (Hz)

cycles/sercond

225
Q

f=?

(frequency)

A

f= 1/T

f=1/(2π)ς(k/m)

f= 1/(2π)ς(g/l)

last one is for pendulums

226
Q

T =?

(three equations)

(period)

A

T= 1/

T = 2π ς(m/k)

T= 2π ς(l/g)

last one is for pendulums

227
Q

Draw first harmonic, second harmonic, and third harmonic. Give equations for each

A

First: L=1(1/2§)

§=2L/1

Second: L=2(1/2§)

§=2L/2

Third: 3(1/2§)

§=2L/3

Therefore, §=2L/n (n is the harmonic #)

§ is wavelength

228
Q

What is equation for standing wave frequency for 2 fixed ends?

A

fn=(n/2L)v

n is 1,2,3, etc

229
Q

Are sound waves transerse or longitudinal?

A

longitudinal, direction the medium particles oscillate is parllel to the direction the wave travels.

230
Q

The speed of sound waves depend on what?

A

medium’s resistnace to compression and density

231
Q

sound waves

the greater the medium’s resistance to compression:

A

the faster sound travels

232
Q

sound waves

The greater the medium’s density is:

A

the slower sound travels

233
Q

What is intensity? What is the unit?

A

Enegy the sound wave transmits per second (power) per unit area

w/m2

w is waatts

234
Q

What is intensity level measured in?

A

decibels! dB

or bel (B)

235
Q

B =?

B is intensity level. tail on B.

A

B = 10log10(I/I0)

If I is multiplied by 10, add 10 to B

If I is divided by 10, subtract 10 from B

Ex: If I is multiplied by 10,000, add 10+10+10+10=40 to B

236
Q

The speed of light =?

A

3 x10 8 m/s

237
Q

Compare wavenlength and frequency of visible light

A

ROYGBV

Red has lowest frequency therefore longest wavelength

Violet has highest frequency, therefore shortest wavelength

238
Q

speed of light =? (formula)

A

c = fς

(fequency * wavelenth)

239
Q

When EM (electromagnetic) waves travel through a vacuum, they travel ___

A

at the same speed

240
Q

E=?

E is photon energy

A

E=hf=h c/ς

h is plank’s constnt, will be given on mcat

241
Q

What does the law of reflection say?

A

The angle of reflection is equal to the angle of incidence (see notes to draw)

242
Q

What is refraction

A

Bending as light hits water (or some other medium)

243
Q

When does the incident ray angle = the refracted ray angle?

A

When incident ray is perpendiuclar to the surface

244
Q

What is index of refraction?

A

How fast light travels through a medium

245
Q

What is the symbol for index of refraction?

A

n

246
Q

equation for index of refraction

n=?

A

n = c/v

speed of light in vacuum/speed of light in medium

247
Q

The greater n is (index of refraction), the ______ light travels through a vacuum

A

slower

248
Q

Law of refraction formula (shell’s law)

A

n1sinØ1=n2sinØ2

If n2 > n1, then the ray will bend toward the normal

if n2<n1>
</n1>

249
Q

What is total internal reflection?

A

what happens when a light ray travels from a medium of high refractive index into one of lower, and if the ray’s angle of incidence exceeds the criticle one

250
Q

What is the exception to big rule 1 with light waves?

A

when light travels through a material, different frequencies have different speeds (this is why we have diff. colors). Diff colors have different refractie indexes - different angles of refraction

251
Q

in concave mirror, f is

A

+

252
Q

in convex mirror, f is

A

-

253
Q

Draw the focal points and c for concave and convex mirrors

A
254
Q

what does c represent in mirrors?

A

center of curvature

255
Q

convex mirrors can only create

A

virtual images

256
Q

real image vs. virtual

A

real: light rays actually focus @position of the image and can b eprojected on a surface

virtual, light rays dont actually focus on apparant location of the image, cannot be projected

257
Q

lens with short focal length refracts ________ than lens with longer focal lenth. shorter focal length also has ______

A

more light

greater power

258
Q

P =?

lens power

A

P = 1/f

259
Q

What determines the brightness of a lightbulb?

A

Power. P = I2R

So current is the biggest factor in the brightness of a lightbulb. The current will go towards path of least resistance, so if it has low resistance, it has stronger current, more power, and brighter lightbulb

260
Q

Electrical PE (U) =?

A

U = k q1q2/r = U = 1/2qV

(charge * voltage)

261
Q

A magnetic force can accelerate a charged particle by:

A

changing direction of particle. It cannot change the magnitude of its velocity

262
Q

Equation describing a charged particle’s motion in a uniform magnetic field

R =

A

R = mv/qB

R is radius, v is velocity, q charge, B magnetic field, m mass

263
Q

Capacitors in series have the same?

Capacitors in parallel have the same?

A

I (current)

voltage

264
Q

How is charge stored on the capacitor?

A

Evenly distributed on the surface

265
Q

Power consumed by a capacitor equation

P =?

A

P = 1/2 qV

266
Q

Volume is directly correlated to what in waves?

A

Amplitude

267
Q

Waves completely out of phase create what kind of interference?

A

Destructive

268
Q

If wavelength decreases in light waves, the angle of separation would ________

A

decrease. they would move closer together

269
Q

Equation for power consumed by a capacitor

A

P = 1/2qV

MCAT (5 decks)

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