Ch 7

Question 1

Four laws of Stellar Structure

Answer 1

1. conservation of mass
2. conservation of energy
3. hydrostatic equilibrium
4. energy transport

Question 2

Conservation of mass

Answer 2

Total mas equal the sum of shell masses

Question 3

Conservation of energy

Answer 3

total luminosity equals the sum of energy generated in all the layers in each shell

Question 4

Hydrostatic equilibrium

Answer 4

the weight on each layer is balanced by the pressure in that layer

Question 5

Energy transport

Answer 5

energy moves from to cool regions by conduction, radiation, or convection

Question 6

One of the basic laws of stellar structure

Answer 6

the weight on each layer must be balanced by the pressure in that layer

Question 7

The law of energy transport says that energy must flow from hot regions to cooler regions either by

Answer 7

1. Conduction
2. Convection
3. Radiation

Question 8

conduction

Answer 8

the process by which thermal energy is transmitted through medium from one particle to another
-heat energy is conducted through the solid In this way

Question 9

Convection

Answer 9

-heat transfer by mass motion of a fluid such air or water when the heated fluid is caused to move away from the source of heat, carrying energy with it.
-Hot liquids rise as they expand under heat (less dense)
Cool liquids fall (relatively denser)
Movement of liquids due to this effect is called the ‘convection current’

Question 10

Convection above a hot surface occurs because hot air ___, becomes ____, and ____

Answer 10

1. expands
2. less dense
3. rises