6: Temperature

Question 1

Kinetic Energy (J)

1) Define
2) Formula
3) 1 J =
4) What happens if temp increases

Answer 1

1) Energy which a body possesses by virtue of being in motion
2) KE = 1/2 mv2
3) 1 Joule = 1 kg m2 s-2
4) The particles move around faster thus exerting higher pressure

Question 2

Define Heat

Answer 2

The Cumulative Total Kinetic Energy of all molecules in a substance

Question 3

Define Temperature

Answer 3

Proportional to the Average Kinetic Energy of all the molecules in a substance
(scalar quantity - magnitude, no direction)

Question 4

1) What happens when we go up within the atmosphere?
In the thermosphere:
2) Temperature
3) Heat

Answer 4

The density of air changes
(number of molecules decrease with substantially height)
2) High energy molecules (due to magnetic field) = high Average Kinetic Energy
3) Low number of molecules = Total Cumulative Kinetic Energy is low

Question 5

Define Specific Heat Capacity of a a substance

Answer 5

The amount of heat required to raise the temperature of 1 kg of a substance by 1 degree

Question 6

Specific Heat Capacity of

1) Water
2) Land
3) Which heats up/cools down quicker due to this

Answer 6

1) 4190 J kg-1 Degree Centigrade
2) <1000 J kg-1 Degree Centigrade
3) Land

Question 7

Water (Initial state, 10* C)
1 kg of water
1) 11 *C
2) 12 *C
2 kg of water
3) 11 *C
4) 10.5 *C

Answer 7

1) 4190 J energy
2) 8380 J energy
3) 8380 J energy
4) 4190 J energy

Question 8

Given a constant heat source

1) Mass
2) Specific Heat Capacity

Answer 8

1) The greater the mass (which energy s distributed), the lower the temperature change
2) The higher the specific heat capacity of the object, the lower the temperature change

Question 9

Temperature Calculation
Find density where:
Pressure is 1013 hPa,
Universal gas constant is 287.05 J kg-1 K-1,
&
Temperature is 30 *C

Answer 9

p = P/RT
   = 1013 x 100 (convert to Pa)
-----------------------
 287.05 x (30 + 273.15) (convert to K)
   = 1.16 kg m-3

check units
p = kg (mass) m-1 s-2 (acceleration)
—————————————————-
(kg m2 s-2 (Joule) kg-1 K-1 (R is J kg-1 K-1) x K
= kg m-3

Question 10

Conduction
1) Define
Give a: 
2) Very good conductor
3) Poor conductor
4) Good insulator

Answer 10

1) Energy transferred by contact between molecules
2) Metals
3) Air
4) Air

Question 11

If the initial state = 10 *C
What would be the final state, if 4190 J energy were added to:
1) 1 kg Water
2) 1 kg Sand

Answer 11

1) 11 *C

2) 15.24 *C

Question 12

Convection

1) Define
2) Where does it occur

Answer 12

1) Transfer of heat by the movement of a fluid (liquid or gas) between areas of different temperature
2) Troposphere, especially in tropics

Question 13

Advection
1) Define
Horizontal advection
2) Warm air come from
3) Cool air come from

Answer 13

1) The transport of a substance or quantity by bulk motion of a fluid. The properties of that substance are carried with it
2) Nullarbor
3) Fremantle doctor (sea breeze)

Question 14

Solar Radiation

1) Define

Answer 14

Radiation is energy travelling as waves or particles (electromagnetic radiation through space)

Question 15

Diurnal Cycle

Answer 15

A diurnal cycle is any pattern that recurs every 24 hours as a result of one full rotation of the planet Earth around its axis

Question 16

Diurnal cycle

When does maximum temperature occur on Earth

Answer 16

3 pm, lag as it takes time for earth to start emitting radiation back

Question 17

Diurnal cycle

When does minimum temperature occur on Earth

Answer 17

6 am, once the sun has set, the earth is emitting more radiation than it is coming in which keeps happening throughout the night until just before sunrise

Question 18

Hottest month

Answer 18

Even though summer solstice is 22nd Dec, it is February or even early March, lag between maximum incoming radiation and maximum temperature

Question 19

Temperature Inversion (Night)

Answer 19

when we have clear cloudless NIGHT with low wind, earth surface gets so cool, that the air on top of the earths surface gets very cold, the air further aloft is warmer
so we have temp increasing with height - radiative inversion.

Question 20

Temperature Inversion (Day)

Answer 20

As land surface warms up, it warms the air above it so the air on top is cooler, during the day it is generally typical to find temperature decreasing with height

Question 21

Control of temperature in troposphere

Altitude

Answer 21

Temperature decreases with higher altitude

Question 22

Control of temperature in troposphere
Clouds
1) Day
2) Night

Answer 22

1) Temperature decreases with higher cloud clover
2) Temperature increases with high cloud cover
(no radiation from sun but from surface)

Question 23

Control of temperature in troposphere
Winds
1) Day
2) Night

Answer 23

1) Temperature decreases with high winds
(if from cool region)
2) Temperature increases with high winds
(higher kinetic energy)

Question 24

Thermometry

Basic Principle 1

Answer 24

Materials expand as temperature increases

Question 25

Thermometry

Basic Principle 2

Answer 25

Resistance to current flow increases as temperature increases

Question 26

Heat transfer occurs…

Answer 26

from hot to cold regions