Physics Flashcards
The SI unit of length. It is defined by taking the fixed numerical value of the speed of light in vacuum c
Meter
The SI unit of mass. It is defined by taking the
fixed numerical value of the Planck constant h to be 6.62607015×10−34 when expressed in the unit J s, which is equal to kg m2 s−1
Kilogram
_____ is the SI unit of time. It is defined by taking the fixed numerical value of the __________ frequency ∆Vcs, the unperturbed ground-state hyperfine transition frequency of the ______________ atom, to be _________ when expressed in the unit Hz,
which is equal to s−1.
Second; Cesium; Cs-133; 9192631770
The SI unit of electric current.
Ampere
The SI unit of thermodynamic temperature
Kelvin
The SI unit of amount of substance.
Mole
The SI unit of luminous intensity in a given
direction. It is defined by taking the fixed numerical value of the luminous efficacy of monochromatic radiation of frequency ____________, Kcd, to be _______when expressed in the unit lm/W.
Candela; 540 Thz; 1/683
A cylinder with platinum-iridium alloy is used to define the kilogram. What is the name of this cylinder?
Le Grand K
What is the cgs unit of force?
dyne
What is the cgs unit of work?
erg
What is the cgs unit of viscosity?
poise
TRUE OR FALSE
When adding or subtracting measured numbers, the answer should reflect the LEAST accurate scale used in the measurements.
TRUE
In the measurement 29.4 cm, what number(s) is the uncertain digit?
4 is uncertain
Which measurement has higher uncertainty?
a. 123.4
b. 120
c. 123
d. 123.45
b. 120
396 has ___ sig. figs,
65432 has ___ sig. figs.
3 ; 5
7609 has ___sig. figs,
5.0004 has ___sig. figs.
4 ; 5
0.00020 has ___ sig. figs.
35.0 has ___ sig. figs.
2 ; 3
0.02 has ___ sig. fig.
0.0026 has ___ sig. fig.
400 has ___ sig. fig.
400. has ___ sig. figs
1 ; 2 ; 1 ; 3
TRUE OR FALSE
In multiplication or division, the resulting answer must be reported with the same number of significant figures as the measurement with the FEWEST significant figures.
TRUE
How many significant figures are in the
number 0.220?
Three, the leading zero is not significant, but the rest are.
How many significant figures should the product of 1.2 x 1.4592 contain?
2
States that every particle attracts every other particle in the universe with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Law of Universal Gravitation
Law of Universal Gravitation
Gravitation Formula
Fg = Gm1m2/r^2
The “triple point” of a substance is that point for which the temperature and pressure are such that:
a. only solid and liquid are in equilibrium
b. only solid and vapor are in equilibrium
c. only liquid and vapor are in equilibrium
d. solid, liquid, and vapor are all in equilibrium
d.
The lowest velocity which a body must have in order to escape the gravitational attraction of a particular planet or other object.
Escape Velocity
Escape Velocity Formula
Ve = √(Gm/r)
Centripetal Force Formula
Fc = mv^2/r
Linear Expansion Formula
ΔL = LoαΔT
α - coefficent of linear expansion
Thermal energy whose transfer to or from a
substance results in a change of temperature
Sensible Heat
Sensible Heat Formula
Q = mcΔT
The heat required to convert a solid into a liquid or vapor, or a liquid into a vapor, without change of temperature.
Latent Heat
The amount of heat required to change 1 g of a substance at the temperature of its melting point from the solid to the liquid state without changing
temperature.
Latent Heat of Fusion
Latent Heat of Fusion of Ice
80cal/g; 144BTU/lb; 334J/g
It is defined as the heat required to change one mole of liquid at its boiling point under standard atmospheric pressure.
Latent Heat of Vaporization
Latent Heat of Vaporization of Water
540cal/g; 970BTU/lb; 2260J/g
States that the total radiant heat power
emitted from a surface is proportional to the fourth power of its absolute temperature.
𝑃 = σT^4A
Stefan-Boltzmann Law
Pendulum Formula
T = 2π√(L/g)
f = 1/T
Simple Harmonic Motion
T = 2π√(m/k)
f = 1/T
Spring
F = kx
E = 1/2(kx^2)
Speed of Sound in Solid
v = √Y/ρ
Y - Young’s Modulus Constant
ρ - density
Speed of Sound in Liquid
v = √K/ρ
K - Bulks Modulus Constant
ρ - density
Speed of Sound in Gas
v = √(γRT/m)
γ - specific heat ratio
R - gas constant
m - in kg/mol
T - Kelvin
Open-end Air Columns
- all harmonics
λ = V/f = 2L/h
Close-end Air Columns
- odd harmonics only
λ = V/f = 4L/h
Audio Frequency Range
20 Hz - 20 kHz
Voice Frequency Range
300 Hz - to 3 kHz
Infrasonic Waves
f < 20 Hz
Ultrasonic Waves are also called as
Supersonic Waves
Ultrasonic Waves Range
f > 20 kHz
Doppler Shift Formula
fo = fs[(V±Vo)/(V±Vs)]
Vo sign if the observer moves toward the source
(+)
Vo sign if the observer moves away from the source
(-)
Vs sign if the source is moving towards the observer
(-)
Vs sign if the source is moving away from the observer
(+)
Index of Refraction Formula
n = Co/V
Speed of Light
c = √(1/μoεo)
μo - permeability of free space, henry/m
εo - permittivity of free space, farad/m
A law stating that the ratio of the sines of the
angles of incidence and refraction of a wave are constant when it passes between two given media
Snell’s Law
Snell’s Law Formula
n1 sin θi = n2 sin θr
A case of refraction where the light ray can actually bend so much that it never goes beyond the boundary between the two media.
Total Internal Reflection
Total Internal Reflection Formula
𝜃𝑐 = sin−1(𝑛2/𝑛1)
The scientific study of sight and the behavior of light, or the properties of transmission and deflection of other forms of radiation.
Optics
Mirror Equation
1/𝑓 = 1/𝑑𝑜 + 1/𝑑i
Magnification
M = hi/ho = -di/do
Radius of Curvature
R = 2f
The focal length of a _________ mirror has a negative value.
convex
The focal length of a _______ mirror has a positive value
concave mirror
The negative value for image distance indicates that the image is a _______ image located _______ the mirror
virtual; behind
The positive value for image distance indicates that the image is a _______ image located _______ the mirror
real; in front of
A positive magnification indicates that the image is
erect
A negative magnification indicates that the image is
inverted
The image produced by a convex mirror of an erect object in front of the mirror is always:
a. virtual, erect and larger than the object
b. virtual, erect and smaller than the object
c. real, erect and larger than the object
d. real, erect and smaller than the object
b.
Lens or Mirror Equation
1/𝑓 = 1/𝑑𝑜 + 1/𝑑i
Magnification
M = hi/ho = -di/do
Radius of Curvature
R = 2f
Len’s Maker Formula
1/f = (n-1) (1/R1 - 1/R2)
R1 - convex
R2 - concave
The type of lens used to cure farsightedness is ______________ lens.
Convex
Farsightedness also known as
Hyperopia
Nearsightedness also known as
Myopia
The focal length of a converging lens has a ________ value.
positive
The focal length of a diverging lens has a ________ value.
negative
Speed of light is constant number __ in calculator.
What unit?
28; m/s
Planck Constant is constant number __ in calculator.
What unit?
06; J/s
Electron charge is constant number __ in calculator.
23
Boltzmann Constant is constant number __ in calculator.
What unit?
25; J/k
Avogadro’s Number is constant number __ in calculator.
What unit?
24; molecules/mole
Gravitational Constant is constant number __ in calculator.
39
The laws of physics are the same for all observers in any inertial frame of reference relative to one another (principle of relativity).
Special Relativity
TRUE OR FALSE:
The speed of light in a vacuum is the same for all observers, regardless of their relative motion or of the motion of the light source.
TRUE
Counterintuitive consequences of Special Relativity
Relativity of Simultaneity
Time Dilation
Length Contraction
Finite maximum speed
Mass-energy Equivalence
Relativistic mass
Consequences of General Relativity
Gravitational Time Dilation
Precession
Light Deflection
Frame Dragging
Two events, simultaneous for one observer, may not be simultaneous for another observer if the observers are in relative motion.
Relativity of Simultaneity
Moving clocks are measured to tick more slowly than an observer’s “stationary” clock.
Time dilation
Objects are measured to be shortened
in the direction that they are moving
with respect to the observer.
Length contraction
Energy and mass are equivalent
and transmutable.
Mass-energy equivalence
Mass-energy equivalence formula
E=mc²
Clocks run slower in deeper gravitational wells.
Gravitational time dilation
Orbits precess in a way unexpected in
Newton’s theory of gravity.
(This has been observed in the orbit of Mercury and in binary pulsars).
Precession
Rays of light bend in the presence of a gravitational field
Light deflection
Rotating masses “drag along” the spacetime around them.
Frame dragging
The universe is expanding, and the far parts of it are moving away from us faster than the speed of light.
Metric expansion of space
Lorentz factor
γ = 1/ √ [1 − (v/c)²]
Lorentz velocity transformation
u’ = (u − v) / [1 − (uv/c²)]
Relativistic doppler effect (frequency)
fo = fs √ [1+ (v/c)]/ [1 − (v/c)]
Relativistic doppler effect (wavelength)
λo = λs √ [1 − (v/c)]/ [1 + (v/c)]
It deals with the study of light and particles at atomic and smaller level
Quantum mechanics
Beta particles are electrons or positrons emitted from a nucleus during beta decay. These particles travel at a speed of _________ of the speed of light
9/10
Alpha particles travel at a speed of
1/10 of the speed of light
= 1/10 c
Gamma particles travel at a speed of
≈ c
de Broglie wavelength formula
λo = h/ mv
h = Planck’s constant (const 06)
Planck’s law formula
Ep = hc / λ = hf
Ep = energy
Formula of frequency
f = c/ λ
Which among the rainbow colors has the longest wavelength and lowest frequency?
Red
Which among the rainbow colors has the shortest wavelength and highest frequency?
Violet
It has a wavelength that is too long to be seen by the naked eye
Infrared
It has a wavelength that is too short to be seen by the naked eye
Ultraviolet
Rydberg’s formula
1/λ = Z² R∞ (1/n1² − 1/n2²)
Z = atomic number
R∞ = Rydberg’s constant
Rydberg’s constant is constant number ____
CONST 16
Lyman series
n2 = 1
Balmer series
n2 = 2
Paschen series
n2 = 3
Bracket series
n2 = 4
Pfund series
n2 = 5
Humphreys series
n2 = 6
States that the current through a conductor between two points is directly proportional to the voltage across the two points.
Ohm’s Law
Ohm’s Law formula
I = V/R
When resistors are connected in series, the formula for total resistance is
Rₜ = R₁ + R₂ + … + Rₙ
Total current in series of resistors
Iₜ = I₁ = I₂ = … = Iₙ
Formula for total voltage across resistors connected in series
Vₜ = V₁ + V₂ + … + Vₙ
Formula for total resistance across resistors connected in parallel
1/ Rₜ = 1/R₁ + 1/R₂ + … + 1/Rₙ
When resistors are connected in parallel, the formula for total current is
Iₜ = I₁ + I₂ + … + Iₙ
Total voltage of resistors connected in parallel
Vₜ = V₁ = V₂ = … = Vₙ
TRUE or FALSE
The lower the resistance, the higher the current flow.
TRUE
Formulas for transformers
Nₚᵣᵢ/ Nₛₑ꜀ = Vₚᵣᵢ / Vₛₑ꜀
IₚᵣᵢNₚᵣᵢ = Iₛₑ꜀Nₛₑ꜀
Rₚᵣᵢ/ Rₛₑ꜀ = (Nₚᵣᵢ/ Nₛₑ꜀)²
Area expansion formula
ΔA = AₒαₐΔT
αₐ = coefficient of area expansion
Coefficient of area expansion
αₐ = 2αₗ
αₗ = coefficient of linear expansion
Volume expansion formula
ΔV = VₒαᵥΔT
αᵥ = coefficient of volume expansion
Coefficient of volume expansion
αᵥ = 3αₗ
αₗ = coefficient of linear expansion
Nuclear sizes are expressed in a unit named
Fermi
Femtometer -> 10⁻¹⁵ m
Lightyear is a unit of
distance
Mirage is due to
unequal heating of different parts of
atmosphere
Stars appears to move from east to west because
the earth rotates from west to east
If two bodies of different masses, initially at rest, are acted upon by the same force for the same time, then both bodies acquire the same __
momentum or impulse
It is not emitted by radioactive substances
neutrons
Sound waves in air are ___
longitudinal
Waves that are perpendicular to the medium
Transverse waves
Waves that are parallel to the medium
Longitudinal waves
Materials for a rain-proof coats and tents owe their water-proof properties to
surface tension
The temperature at areas higher than sea level is __ than areas closer to sea level
lower
It takes much longer to cook food in the hills than in the plains, because in the hills the atmospheric pressure is _____ than that in the plains and therefore water boils at a temperature _____ than 100 deg C causing an increase in cooking time
lower; lower
Intensity of sound at a point is _____________ its distance from the source
inversely proportional to square of
Of the four locations mentioned below the highest inside temperature will be attained in the pressure cooker operated with the pressure valve open.
a. at sea level
b. at the top of Mt. Everest
c. at a place below sea level
d. in an aeroplane flying at a height of 10km
with inside pressure maintained at the sea level
c. at a place below sea level
Mercury is commonly used as a thermodynamic fluid rather than water because
mercury has greater visibility than water
Impulse is equal to __ (formula)
Force x time
Momentum is equal to __ (formula)
mass x velocity
An object’s change in momentum is equal to its ___
impulse
Pascal’s principle
Pᵢₙ = Pₒᵤₜ
Fᵢₙ/Aᵢₙ = Fₒᵤₜ/Aₒᵤₜ
Bernoulli equation
P₁ + ρgh₁ + 1/2 ρv₁² = P₂ + ρgh₂ + 1/2 ρv₂²
It is the ratio of the amount of charge Q on either conductor to the potential difference V between the conductors.
Capacitance
Capacitance formula
C = Q/V
C = capacitance
Q = charge
V = voltage/ potential difference
Formula of total voltage V for capacitors connected in series
Vₜ = V₁ + V₂
Total charge Q of capacitors in series formula
Qₜ = Q₁ = Q₂
Total capacitance C formula for capacitors in series
1/Cₜ = 1/C₁ + 1/C₂
For capacitors in parallel, the formula for total charge Q is
Qₜ = Q₁ + Q₂
Total voltage V of capacitors in parallel formula
Vₜ = V₁ = V₂
Formula of total capacitance C for capacitors connected in parallel
Cₜ = C₁ + C₂
