February Review - Vesna Questions

Question 1

how long is our suns life?

Answer 1

10 billion years, it has 5 billion to go.

Question 2

what does our sun burn in its core?

Answer 2

hydrogen

Question 3

suns life:

Answer 3

1. main sequence
2. red giant
3. helium core burning
4. planetary nebula leaves white dwarf behind

Question 4

what is heavier? higher mass small white dwarf or lower mass big white dwarf?

Answer 4

higher the mass, heavier it is.

Question 5

are binary stars common?

Answer 5

over half are.

Question 6

what is the most combustable element in the universe?

Answer 6

carbon.

Question 7

how old is our universe?

Answer 7

13.8 billion yrs old.

Question 8

what are the two types of star clusters?

Answer 8

open and globular.

Question 9

what is a supernova called if it has no luminosity?

Answer 9

standard candle.

Question 10

sun’s white dwarf will be the size of?

Answer 10

Earth.

Question 11

what is an accretion disk?

Answer 11

surrounds white dwarf while it’s binary star looses mass.

Question 12

what is a nova?

Answer 12

when the temperature of an acreded matter eventually becomes hot enough for hydrogen fusion. (which is temporary brightening)

Question 13

the bigger the star, the ___ they live, and the smaller the star the ___ they live.

Answer 13

shorter, longer.

Question 14

out of OBAFGKM, what star is our sun?

Answer 14

G.

Question 15

which hr diagram is the oldest and which is the youngest?

Answer 15

the one with the most is the oldest, and the one with the least is the youngest.

Question 16

what do cluster hr diagrams give us?

Answer 16

snapshot of stellar evolution.

Question 17

does iron fuse into anything? how big is an iron nucleus?

Answer 17

no, and huge.

Question 18

what is the mass of a white dwarf?

Answer 18

mass of sun.

Question 19

size of white dwarf?

Answer 19

size of earth.

Question 20

size of neutron star?

Answer 20

up to 3 solar masses.

Question 21

what is the most dense object?

Answer 21

neutron star.

Question 22

what is a pulsar?

Answer 22

rotating neutron star. –> “clocks of the universe”

Question 23

the majority (99%) of supernovas energy are?

Answer 23

neutrinos.

Question 24

what is the speed of light?

Answer 24

671 million miles/hr.

Question 25

what is the equivalence principle?

Answer 25

the effects of gravity are exactly equivalent too the effects of acceleration.

Question 26

explain gravity.

Answer 26

more mass = more distortion because mass bends space time.

Question 27

what is the essence of general gravity?*

Answer 27

matter tells space how to curve, space tells matter how to move.

Question 28

what is gravitational lensing?

Answer 28

mirage of a galaxy because light follows the straightest path possible, gravitational lensing occurs when it is not in a perfect line.