Conceptual Physics- Universal Dwelling Unit Test

Question 1

What is the formula for area (of a floor plan/living space).

Answer 1

length (feet or meters) x width (feet or meters) = area (square feet or square meters)

Question 2

Give the total living space of a house that is 24x38 feet. Show work

Answer 2

24x38= 912 ft2
600+160+120+32= 912 ft2

Question 3

What does a heating and cooling curve look like?

Answer 3

a bell shape or a upside-down hyperbola

Question 4

Larger windows transfer blank heat

Answer 4

more

Question 5

How much heat does a 5x7 window transfer compared to a 2x3 window?

Answer 5

5x7 35 5.8333333333…
—— = —- = ———————
2x3 6 1
The 5x7 window transfers 5.83333…. times as much as the 2x3 window

Question 6

How does insulaton affect how heat is transferred

Answer 6

CD: air spaces- air is a bad conductor because it is a gas
CV: air spaces are too small for convection currents
Radiation: shiny or light colored surfaces reflect heat transferred by radiation.

Question 7

How do you find combined R-Values

Answer 7

addition

Question 8

Explain how you could reach R-35 using: R-10; R-5; R-7; and R-15? List 4 methods

Answer 8

Three layers of ten, layer of five
two layers of fifteen, layer of five
seven layers of five
five layers of seven
two layers of ten, layer of fifteen
layer of fifteen, layer of ten, two layers of five

etc. anything that adds up to 35

Question 9

How does heat enter leave or travel through a building?

Answer 9

CD: transfers heat through walls by direct contact of atoms
CV: circulates heat in house- hot air rises
R: transfers heat to outside and roof of building or through windows

Question 10

Why does hot air rise? (mention Density)

Answer 10

Hot air is less dense than cold air. Liquids and GASES layer by density with densest objects at bottom (in this case cooler air).

Question 11

What is the density formula? Provide units

Answer 11

grams/centimeters^3

Question 12

Calculate density of cube: 6x2x9; weighs 40 grams

Answer 12

6x2x9= 108 (12x9 (18+90))
108/40= 2.7g/cm^3

Question 13

What is heat?

Answer 13

heat is the total kinetic energy in molecules

Question 14

What is temperature?

Answer 14

measurement of average kinetic energy (how fast they are moving/speed)

Question 15

Give two examples of conduction:

Answer 15

hand on a hot pan, molecules in a hot wall touching each other, pan being heated by stove (touching the stove)

Question 16

Give two examples of convection:

Answer 16

wind, radiator, hot air in house,

Question 17

Give two examples of radiation:

Answer 17

fire heating room, sun hitting the house

Question 18

Two examples of Conductors:

Answer 18

metal; glass; solids in general

Question 19

Two examples of insulators:

Answer 19

styrofoam (with air pockets); down; gases or pockets of gases within solids in general

Question 20

Two materials that reflect heat.

Answer 20

aluminum, paper, white shirt

Question 21

two materials that absorb heat:

Answer 21

dull/dark cloth; leather (not white); asphalt; black desk;

Question 22

What is thermal equilibrium?

Answer 22

when two liquids/solids/gases of differing temperatures are in contact with each other, they with gradually become the same temp.

Question 23

What direction does heat go?

Answer 23

from warmer to colder; except radiation, which goes in all directions

Question 24

If it is: 38 degrees outside; 63 inside a gym; and a cool water bottle inside the gym is 47; then where will the heat go?

Answer 24

from the gym to the outside and the bottle.

Question 25

How do liquids and gases layer?

Answer 25

from densest (at the bottom) to least dense

Question 26

If something1 is 1.3 g/cm3, something2 is 3.2, and something3 is .3, how will they layer from top to bottom?

Answer 26

something3
something1
something2

Question 27

What is the law of conservation of energy?

Answer 27

energy cannot be destroyed or created; it can only change form

Question 28

Why does an iceberg have more heat than a pot of boiling water?

Answer 28

More molecules-more heat energy. Even though the temperature is less, there is more overall movement (kinetic energy) because there are so many molecules

Question 29

potential energy

Answer 29

stored energy (stretched rubber band)

Question 30

thermal energy

Answer 30

heat energy (fire/burning)

Question 31

kinetic energy

Answer 31

energy of movement (released rubber band flying through air)

Question 32

energy

Answer 32

the force that makes matter move or change; or the ability to make something move or go; many types

Question 33

km

Answer 33

kilometer

Question 34

of meters in a km

Answer 34

1000

Question 35

cm

Answer 35

centimeter

Question 36

of cm in a meter

Answer 36

100

Question 37

mm

Answer 37

millimeter

Question 38

how many mm in a meter?

Answer 38

1000

Question 39

how many mm in a cm?

Answer 39

10

Question 40

conduction:

Answer 40

heat transfer through direct contact of molecules

Question 41

conductor

Answer 41

substance that allows heat to transfer easily

Question 42

convection

Answer 42

heat transfer in groups of molecules; caused by differences in density; groups of molecules rise and fall due to density

Question 43

radiation

Answer 43

heat transfer by electromagnetic waves

Question 44

density

Answer 44

amount of matter in a unit of space; mass divided by volume; how compact something is

Question 45

insulator

Answer 45

restricts heat transfer; a material that does not allow heat to transfer easily through it