Astrophysics

Question 1

Intensity Ratio

Answer 1

1_A/1_B = 2.512^MB-MA

Question 2

Magnitude Difference

Answer 2

M_A-M_B = 2.5log(1_A/1_B)

Question 3

Small Angle Formula

Answer 3

angular diameter-arcseconds/206265 = linear diameter/distance

Question 4

Circular Velocity

Answer 4

V_C = squareroot(GM/r-meters)

M = mass of central body (kg)

G = 6.67x10^-11 m³/s²kg

* Answer in m/s

Question 5

Compare LGP

Answer 5

LGP_A/LGP_B = (D_A/D_B)²

D = diameter

* Answer in times (x)

Question 6

Resolving Power

Answer 6

a = 11.6/D(cm)

D = diameter (cm)

* Answer in arcseconds

Question 7

Magnification

Answer 7

M = F_O/F_E

F_O = focal length of objective

F_E - focal length of eyepiece

Question 8

Wien’s Law

Answer 8

~_max = 3,000,000/T-degrees Kelvin

* Answer in nm

~_max = .2987/T x 10⁸Å

T = 2.9x10⁸Å/peak ~

Question 9

Stefan-Boltzmann Law

Answer 9

E = σT⁴(J/s/m²)

T = K

σ = 5.67 x 10^-8J/m²s degree⁴

* Answer in J

Question 10

Doppler Formula

Answer 10

V_r/c = triangle~/~_o

V_r = radial velocity

c = 300,000 km/s

triangle~ = change in ~

~_o = observed ~

(lmaoo you’re prob laughing when u see this)

Question 11

Fusion Explained

Answer 11

E = mc²

m = kg

c = 3x10⁸ m/s

Question 12

Distance to Star

Answer 12

d = 206,265/p-arcseconds

p=parallax

* Answer in AU

Question 13

F Ratio

Answer 13

focal length(mm)/objective diameter(mm)

Question 14

Distance Modulus

Answer 14

m_v - M_v = -5 + 5log(d)

d = 10 ^m_V-M_V+5/5 = pc

Question 15

Luminosity of Star

Answer 15

L/L_o = (R/R_o)(T/T_o)

* Answer in times (x)

Question 16

Mass of Binary System

Answer 16

M_A + M_B = a³/p²

M= solar masses

p = orbital period (yrs)

a = AU

Question 17

Kepler’s 3^rd Law

Answer 17

p² = a³

p = orbital period (yrs)

a = distance (AU)

Question 18

Mass-Luminosity Relation

Answer 18

L = M^3.5

M = star mass in M_o

* Answer in times (x)

Question 19

Life Expectancy

Answer 19

T = 1/M^2.5

M = star mass in M_o

* Answer in O lifetimes x 10 billion = years

Question 20

Schwarzschild Radius

Answer 20

R_S = 2GM/C²

G = 6.67 x 10^-11 m³/s²kg

C = 3 x 10⁸ m/s

M = mass (kg)

* Answer in m

Question 21

Hubble Law

Answer 21

V_r = Hd

V_r = velocity of recession of galaxy (km/s)

H = 20km/s/Mpc

d = distance (Mpc)

Question 22

Redshift

Answer 22

Z = triangle~/~_o

triangle~ = change in ~

~_o = unshifted ~

Question 23

Age of Universe

Answer 23

T_U = 1/H x 10¹²years

H = 70 km/s/Mpc

* Answer in years

Question 24

Distance-Rate-Time

Answer 24

d = rt

r = d/t

t = d/r

Question 25

Newton’s Law of Gravity

Answer 25

F = G^{m₁m₂/r^2}

G = 6.67 x 10^-11 m³/s²kg

m₁m₂ = masses of objects in kg

r = distance between the two masses (m)

F = the strength of the gravitational force (N)

Question 26

Kepler’s 1^st Law (Eccentricity)

Answer 26

e = c/a

Question 27

Ratio

Answer 27

distance/(size/separation)

Question 28

Frequency

Answer 28

v = c/~

Question 29

1 AU

Answer 29

1.495979 x 10¹¹m

Question 30

1 parsec (AU)

Answer 30

206,265 AU

Question 31

1 parsec (m)

Answer 31

3.085678 x 10¹⁶m

Question 32

1 parsec (light years)

Answer 32

3.261633 light years

Question 33

1 light year

Answer 33

9.46053 x 10¹⁵m

Question 34

c, or the speed of light

Answer 34

2.997925 x 10⁸m/s

Question 35

G, or the gravitational constant

Answer 35

(6.67 x 10^(-11)) + (m³/s²)/kg

Question 36

M₊

Answer 36

5.976 x 10²⁴kg

Question 37

R₊

Answer 37

6,378.164 km

Question 38

M_o

Answer 38

1.989 x 10³⁰kg

Question 39

R_o

Answer 39

6.9599 x 10⁸m

Question 40

L_o

Answer 40

3.826 x 10²⁶kg

Question 41

M of the Moon

Answer 41

7.350 x 10²² kg

Question 42

R of the Moon

Answer 42

1738 km

Question 43

M of H atom

Answer 43

1.67352 x 10^-27 kg

Question 44

1 arc minute (1’)

Answer 44

1/60^o

Question 45

1 arc second (1”)

Answer 45

1/60’

Question 46

1 Megaton

Answer 46

1,000k000 of TNT = 4.5 x 10¹⁵ J

Question 47

Gravity

Answer 47

6.67x10^-11Nm²/kg²

Question 48

Force

Answer 48

F = G x m₁m₂/r²

Question 49

Eccentricity

Answer 49

e² = 1 -b²/a²

Question 50

Barycenter

Answer 50

ma/mb = rb/ra

m = mass

r = distance

Question 51

Keplar’s 3^rd Law

Answer 51

p2 = (4π^2/GM)a3

G = gravitational constant

M = mass of centeal object

P = solar years

Question 52

Keplar’s 2^nd Law

Answer 52

rotation of the a planet around a focal point results in the same time lapse passed over two opposite, but similar given areas. This proves acceleration as we near the focal point

Question 53

1a supernovae

Answer 53

caused by white dwarves gaining mass of over 1.4 solar masses from its companion in a binary system

all 1a supernovaes have the same brightness and can determine intergalatic distances. They are brighter than type II

Question 54

Type II supernovae

Answer 54

stars must be 8+ solar masses. Iron production because as elements run out for fusion. Heavy elements > atomic #26 are created in supernovae

Question 55

Pulsars

Answer 55

stars core must be 1.4-3.2 solar masses. Emits beans of radiation at magnetic poles.

Question 56

H-R Diagram

Answer 56

relates the absolute magnitudes and luminosities of stars with spectral types and temps. Can reveal characteristics in stars and predict locations of new stars. Measured in kelvin or spectral class (O B A F G K M)