Shared Flashcard Set

Details

physics etc
hell on earth
123
Science
Professional
07/08/2012

Additional Science Flashcards

 


 

Cards

Term
Examples of simple harmonic motion
Definition
pendulums and springs
Term
Definition of simple harmonic motion
Definition
a particle or mass oscillates about an equilibrium position and is subject to linear restoring force
Term
Hooke's law = Equation for a spring force
Definition
F = -kx
F is restoring force, k is constant and x is displacement from equilibrium
Term
Acceleration of spring
Definition
a = (-w^2)x
w is angular frequency
Term
Give the equation for w and state what it stands for
Definition
w is the angular frequency of a spring
w = 2(pi)f = sqrt(k/m)
Term
How is angular frequency measured? Give examples for 45*, 90*, 180*, and 360*.
Definition
In radians: 45*=pi/4
90* = pi/2
180* = pi
360* = 2pi
Term
other equivalents for angular frequency
Definition
w = 2(pi)f = 2(pi)/T = sqrt(k/m)
Term
Equation for a period (oscillation period)
Definition
The time it takes to complete one cycle is T = 1/f
Term
Potential energy of a spring
Definition
U = 1/2kx^2
Term
Kinetic energy of a spring
Definition
K = 1/2mv^2
Term
Simple pendulum restoring force equation
Definition
F = -mg(sin(theta))
Term
angular momentum of a pendulum
Definition
w = 2(pi)f = sqrt(g/L)
Term
Force constant k for a mass-spring system
Definition
spring constant k
Term
force constant k for a simple pendulum
Definition
mg/L
Term
period T for a mass spring system
Definition
2(pi)sqrt(m/k)
Term
period T for a simple pendulum
Definition
2(pi)sqrt(L/g)
Term
angular frequency of a simple pendulum
Definition
w = 2(pi)f = sqrt(g/L)
Term
frequency f for a mass spring system
Definition
1/T or w/2(pi)
Term
frequency f for a simple pendulum
Definition
1/T = w/2(pi) = (1/2pi)(sqrt(g/L))
Term
kinetic energy K of a simple pendulum
Definition
KE = 1/2mv^2
Term
Maximum kinetic energy occurs where in a spring system?
Definition
at x = 0, kinetic energy is at its maximum
Term
Maximum kinetic energy k occurs where in a simple pendulum?
Definition
at theta = 0, kinetic energy will be at its maximum in a simple pendulum system
Term
Potential energy U of a simple pendulum
Definition
U = mgh
Term
Maximum potential energy of a simple pendulum occurs where?
Definition
at the maximum value of theta, the potential energy will be at its maximum
Term
Where will the maximum potential energy occur in a spring system?
Definition
The maximum potential energy will occur when the maximum displacement has been reached, x = +/-X
Term
Where will maximum acceleration be obtained in a simple pendulum?
Definition
At the maximum value of theta, the maximum acceleration will occur in a simple pendulum
Term
Where will maximum acceleration be obtained in a mass-spring system?
Definition
At the maximum displacement, the acceleration is the greatest.
Term
Displacement of a particle at y on a wave can be plotted against each point x as it moves along; give this in an equation
Definition
y = Ysin(kx-wt)
Term
define Y
Definition
simple amplitude, or maximum displacement
Term
define k as it relates to waves (not spring constant)
Definition
k is wavenumber
Term
define lambda as it pertains to waves
Definition
lambda is the wavelength of a wave
Term
define f, frequency, as it pertains to a wave
Definition
f is the number of waves that pass a stationary point per second
Term
define v, velocity, as it pertains to a wave
Definition
v is the speed of the wave as it relates to frequency and wavelength
Term
Give the equation and equivalent equations for velocity, v, of a wave
Definition
v = f(lambda) = (lambda)/T = w/k
Term
give equation for k, wavenumber
Definition
k = 2(pi)/lambda
Term
Nodes on a wave
Definition
points where amplitude is zero at all times
Term
Antinodes on a wave
Definition
points midway between nodes; here, the point on the wave fluctuates with maximum amplitude
Term
Another way to describe frequency of a pendulum
Definition
f = 1/2pi*sqrt(g/L)
Term
When is a pendulum resonating? This is also true of waves.
Definition
A pendulum or wave is resonating when some periodic force applied to it is about equal to the system's natural frequency.
Term
When a system is resonating, what can be said about its amplitude of oscillation?
Definition
Amplitude will be at its maximum.
Term
c =?
Definition
3.0 x 10^8 m/s
Term
what is speed of sound directly proportional to?
Definition
bulk modulus
Term
what is the speed of sound inversely proportional to?
Definition
the density of the medium through which it travels
Term
Through which medium does sound travel the fastest?
Definition
solids
Term
Through which medium does sound travel the slowest?
Definition
gases
Term
What is the speed of sound in air at 0*C?
Definition
331 m/s
Term
What is the audible range of sound?
Definition
20-20,000 Hz
Term
Give definitions of sound below 20 Hz and sound above 20,000 Hz
Definition
infrasonic is below 20 Hz, ultrasonic is above 20,000 Hz
Term
How is sound propagated?
Definition
Particles of a material are perturbed to form waves of particles with small differences of compression and decompression (or rarefaction)
Term
How is intensity of sound measured? Describe and give equation
Definition
Intensity is the rate per unit area of which energy transfer occurs perpendicular across a surface.

I = P/A
Term
What are the SI units of intensity, I?
Definition
Watt/m^2
Term
Give equation for determining the power of the sound wave as it hits some surface.
Definition
P = IA
Term
Intensity is ________ proportional to (amplitude^2)
Definition
directly propertional!
Term
Intensity is _________ proportional to (distance^2) from the source of sound
Definition
inversely proportional!
Term
How do we describe sound levels?
Definition
sound level = beta, decibels
Term
Give the equation for decibels
Definition
beta = 10 log (I/Io)
Term
What is I/Io?
Definition
This is the ratio of intensity at a certain point to the original intensity
Term
Give equation for figuring out difference sound levels
Definition
Beta(f) = Beta(i) + 10 log(If/Io)
Term
Describe If/Io
Definition
this is the ratio of final intensity of original intensity
Term
newtons first law
Definition
also called law of inertia; a body in motion or at rest will remain so unless acted upon by a net force
Term
newton's second law (words + math)
Definition
when a net force is applied to a body of mass the body will accelerate in same direction as that force.

Expressed mathematically as F = ma (1N = 1 kg*m/s^2)
Term
Newton's third law (words + math)
Definition
if a body A exerts a force on a body B then B will exert a force back onto A that is equal in magnitude (but opposite direction) [law of action and reaction]

Fb = -Fa
Term
Newton's law of gravitation; what other law does this resemble?
Definition
F = Gm1m2/r^2
resembles coulomb's law: F = kq1q2/r^2
Term
What is the formula for acceleration of uniform circular motion?
Definition
a(c) = v^2/r
Term
What is the formula for mass of uniform circular motion
Definition
F(c) = mv^2/r
Term
What is the first condition of equilibrium?
Definition
an object is in translational equilibrium when the sum of forces acting on it are counterbalanced by the sum of forces from an opposite direction [SigmaF = 0]
Term
Is displacement dependent on path?
Definition
no, all that matters is the net distance traveled.
Term
Average velocity
Definition
v = delta x / delta t
Term
name all five equations for linear motion
Definition
v = vo + at
delta x = vot +1/2at^2
v^2 = vo^2 + 2a(delta x)
v(avg) = (vo+v)/2
delta x = vt = ((vo + v)/2)t
Term
projectile motion: vertical component of velocity
Definition
vsin(theta)
Term
projectile motion: horizontal component of velocity
Definition
vcos(theta)
Term
cos 0
Definition
1
Term
cos 30
Definition
(root3)/2
Term
cos 45
Definition
1/root2
Term
cos 60
Definition
1/2
Term
cos 90
Definition
0
Term
cos 180
Definition
-1
Term
sin 0
Definition
0
Term
sin 30
Definition
1/2
Term
sin 45
Definition
1/root 2
Term
sin 60
Definition
(root3)/2
Term
sin 90
Definition
1
Term
sin 180
Definition
0
Term
young's modulus
Definition
Y = (F/A) / delta l / lo
Term
sheer modulus
Definition
S = (F/A) / x/h
Term
electric potential energy U of a charge q
Definition
at a point in space, the potential energy is the amount of work required to move it from infinity to that point

U = q(deltaV) = qEd = (kq1Q)/r
SI: Joule
Term
Electric potential
Definition
this is the amount of work required to move a positive test charge, qo, from infinity to a particular point divided by the test charge:

V = W/qo (SI: Volt = J/C)
Term
Voltage, V = ?
Definition
V = W/q, = kq/r
Term
Archimede's principle: explain and give equation
Definition

The bouyant force = weight of the displaced fluid

 

Fbuoyant = ρfluid g vsubmerged

Term
Bernoulli's equation
Definition
P + 1/2ρv2 + ρgh = constantt
Term
Continuity equation
Definition
v1A1 = v2A2
Term
Guage pressure
Definition
Pg = Pabsolute - Penvironment
Term
Specific gravity
Definition

ρsubstance / ρwater

 

There are no units for specific gravity! (the two rho's cancel one another)

Term
Aboslute pressure in a flui due to gravity somewhere below the surface is given by this equation
Definition
P = Po + ρgh
Term
Describe the force felt by a particle in a magnetic field
Definition
F = qvBsin(θ)
Term
Define the magnetic field B through a loop of wire (solenoid)
Definition
B = μoi/2r
Term
Define the magnetic field B around a straight wire
Definition
B = μoi/2πr
Term
Kirchoff's first law
Definition
At any junction within a circuit, the sum of current flowing into that point must equal the current leaving
Term
Kirchoff's second law
Definition
The sum of voltage sources equals the sum of voltage drops around a closed circuit loop
Term
Describe the fundamental frequency 
Definition
This is the first harmonic; it has the lowest frequency and the longest wavelength of a standing wave supported in a given length of string
Term
Describe wavelength (λ) in terms of L and n (L is length of string and n is some whole number interger 1, 2, ...)
Definition
λ = 2L / n
Term
describe frequency f of a string using n, v, and L
Definition
f = nv / 2L
Term
describe frequency of a string, f, using v and λ
Definition
f = v/λ
Term
What is the SI unit of a magnetic field, B?
Definition
1 Tesla = 1 NS/mC
Term
Define 1 gauss in terms of Teslas
Definition
1 gauss = 1 x 10-4 Tesla
Term
what are the three conditions necessary for a particle to feel the force of a magnetic field?
Definition

1. The particle must have a nonzero charge

2. The particle must have some velocity

3. The particle must not be travelling parallel or antiparallel to the current-carrying wire.

Term
In what direction will a particle travel when placed in a uniform magnetic field?
Definition
It was travel in a circle
Term
If Fmagnetic = m*a, and the particle is undergoing centripetal acceleration in the magnetic field, then qvB = ?
Definition
qvB = m*(v2/r) since centripetal acceleration = v2/r
Term
What is the radius of the circle a particle will travel when placed in a uniform magnetic field?
Definition
r = mv/qB
Term
What if we were to place a current-carrying wire into a magnetic field? How would we interpret the magnitude of force?
Definition
F = ILBsinθ
Term
In which direction do positive charges flow with regard to a current?
Definition
Positive charges flow with a current, negative charges flow against it. 
Term
Define resistance with respect to the resistivity of a material
Definition

ρ is resistivity of a material

 

R = ρL / A

 

L is length of resistor

A is cross sectional area of resistor

Term
Is the voltage drop across a resistor directly or inversely proportional to the current passing through it?
Definition
Directly proportional--this is the basis of Ohm's law
Term
Define voltage drop in an equation
Definition

Voltage drop = current x resistance

 

V = IR

 

*OHM'S LAW*

Term
SI unit of current?
Definition

I = Δq/Δt

I = C/s

C/s = ampere (SI unit of current)

Term
SI unit of resistance?
Definition

Ohms! 

 

1 Ω = V/A (volts/amperes)

Term

Find the heat given off by a resistor in one minute, given 3 amps and a resistance of 5 ohms. 

step 1: equation

step 2: give equivalent

step 3: solve

Definition

Energy = Power x time

E = Pt

 

P = I2R

(plug in)

E = I2Rt

E = (32)(5Ω)(60seconds)

E = 9 x 300 = 2700 Joules

Term
Give SI units of a Farad, F
Definition
C2s2/kg2m2
Term
Give current RMS in equation
Definition
Irms = Imax/√2
Term
Give voltage RMS in equation
Definition
Vrms = Vmax/√2
Term
Give equation for electric power gained from current and resistance
Definition

P = I2R

 

As resistance increases, energy dissipates at a faster rate

Term
Give equation for entropy change given a reversible process
Definition

ΔS = Q/T = HL + m/T

 

HL is latent heat

m is mass

T is constant temperature

Supporting users have an ad free experience!