Physics Model 1 Learned Topic

MAGNETIC FIELD OF A WIRE

B = (u0*I)/(2*pi*r)

MAGNETIC FORCE

F = q*v*B*sin(theta)

CIRCULAR MOTION IN MAGNETIC FIELD

q*v*B = m*v^2/r

MASS OF CHARGED PARTICLE

m = (q*B*r)/v

VELOCITY SELECTOR

qE = qvB

ELECTRIC FIELD FOR NO DEFLECTION

E = vB

RIGHT-HAND RULE

Thumb = current, fingers = magnetic field

CURRENT UPWARD

Left side = out of page (⊙), Right side = into page (⊗)

REGION 1 TWO UPWARD CURRENTS

Same direction

REGION 2 TWO UPWARD CURRENTS

Opposite directions

REGION 3 TWO UPWARD CURRENTS

Same direction

MAGNETIC FIELD CANCELLATION

B1 = B2

PHOTOELECTRIC EFFECT PHOTON ENERGY

E = hc/lambda

PHOTOELECTRIC EQUATION

Ephoton = phi + Kmax

WORK FUNCTION

Minimum energy needed to remove an electron

PHOTOELECTRON EMISSION

Ephoton > phi

NO PHOTOELECTRON EMISSION

Ephoton < phi

MAXIMUM KINETIC ENERGY

Kmax = Ephoton - phi

STOPPING POTENTIAL

Kmax = eV

PHOTOELECTRON SPEED

K = (1/2)mv^2

SHORTER WAVELENGTH

More energy

LONGER WAVELENGTH

Less energy

PHOTOELECTRIC EFFECT TRIGGERS

Work function, wavelength, stopping potential, photoelectrons

RADIOACTIVE DECAY

N = N0*e^(-lambda*t)

HALF-LIFE EQUATION

N = N0*(1/2)^(t/T1/2)

MASS DECAY

m = m0*(1/2)^(t/T1/2)

HALF-LIFE

Time required for half the sample to decay

UNKNOWN REMAINING MASS

Use half-life equation

UNKNOWN TIME

Use logarithms

LOG RULE

ln(a^b) = b*ln(a)

ALPHA DECAY

A - 4, Z - 2

ALPHA PARTICLE

4He2

BETA MINUS DECAY

A same, Z + 1

BETA PLUS DECAY

A same, Z - 1

GAMMA DECAY

A same, Z same

ALPHA IDENTIFICATION

Mass number decreases by 4 and atomic number decreases by 2

BETA MINUS IDENTIFICATION

Mass number unchanged and atomic number increases by 1

BETA PLUS IDENTIFICATION

Mass number unchanged and atomic number decreases by 1

GAMMA IDENTIFICATION

Mass number unchanged and atomic number unchanged

WAVE EQUATION

v = f*lambda

WAVELENGTH

lambda = v/f

HIGHER FREQUENCY

Shorter wavelength

LOWER FREQUENCY

Longer wavelength

SNELL'S LAW

n1*sin(theta1) = n2*sin(theta2)

CRITICAL ANGLE

sin(thetac) = n2/n1

ANGLE OF INCIDENCE

Angle between incoming ray and normal

ANGLE OF REFRACTION

Angle between refracted ray and normal

LIGHT ENTERING HIGHER n

Bends toward normal

LIGHT ENTERING LOWER n

Bends away from normal

AIR TO OIL

Refracted angle smaller

OIL TO AIR

Refracted angle larger

TOTAL INTERNAL REFLECTION

Higher n to lower n

CRITICAL ANGLE TRIGGERS

Reflection interna total, angulo limite

REFRACTION TRIGGERS

Angulo de incidencia, angulo de refraccion

REFRACTIVE INDEX

n = c/v

LIGHT SPEED IN MEDIUM

v = c/n

SPEED OF LIGHT

c = 3*10^8 m/s

HIGHER REFRACTIVE INDEX

Lower light speed

DE BROGLIE WAVELENGTH

lambda = h/(mv)

PLANCK CONSTANT

h = 6.63*10^-34 J*s

DE BROGLIE TRIGGERS

Matter wave, particle wavelength

PLANE MIRROR IMAGE

Always virtual

PLANE MIRROR IMAGE SIZE

Same size as object

PLANE MIRROR IMAGE

Upright

PLANE MIRROR IMAGE DISTANCE

Same distance behind mirror as object is in front

CONVEX MIRROR

Always virtual

DIVERGING LENS

Always virtual

CONCAVE MIRROR

Can be real or virtual

CONVERGING LENS

Can be real or virtual

SPHERICAL WAVE INTENSITY

I proportional to 1/r^2

INTENSITY-DISTANCE EQUATION

I1*r1^2 = I2*r2^2

DOUBLE DISTANCE

Intensity becomes 1/4

GRAVITATIONAL FORCE

F = G*M*m/r^2

ORBITAL PERIOD

T^2 = (4*pi^2*r^3)/(G*M)

ORBITAL RADIUS

r = cuberoot[(G*M*T^2)/(4*pi^2)]

ORBITAL ENERGY

E = -(G*M*m)/(2*r)

GRAVITATIONAL POTENTIAL ENERGY

U = -(G*M*m)/r

SATELLITE HEIGHT

h = r - RT

ENERGY TO CHANGE ORBITS

dE = Ef - Ei

ORBIT CHANGE EQUATION

dE = (G*M*m/2)*(1/ri - 1/rf)

HIGHER ORBIT

Less negative energy

MOVING SATELLITE OUTWARD

Requires added energy

CIRCULAR ORBIT TRIGGER

Use orbital period equation

SATELLITE TRIGGERS

Orbit, period, satellite, circular trajectory

SYMMETRY AT CENTER OF EQUILATERAL TRIANGLE

Net force = 0

TRAYECTORIA CIRCULAR

Use centripetal force

CAMPO MAGNETICO + CHARGED PARTICLE

Use qvB

NO SE DESVIA

Electric force = magnetic force

SEMIDESINTEGRACION

Use half-life equation

FUNCION DE TRABAJO

Use photoelectric effect equations

LONGITUD DE ONDA + ELECTRON

Use Ephoton = hc/lambda

ANGULO LIMITE

Use critical angle equation

INDICE DE REFRACCION

Use Snell's Law

FREQUENCY + SPEED + WAVELENGTH

Use v = f*lambda

SATELLITE + PERIOD

Use orbital period equation

SYMMETRIC FORCES

Net force = 0