Final Numbers To Know

Question 1

Watts per horse power

Answer 1

746

Question 2

Watts per human power

Answer 2

100

Question 3

Melting/freezing temperature of water

Answer 3

273.15 K

Question 4

Boiling point of water at Earth’s atmospheric pressure

Answer 4

373.15 K

Question 5

Mechanical efficiency of most engines

Answer 5

20%

Question 6

Electrical efficiency of most electrical motors and electrical generators

Answer 6

90%

Question 7

Age of the universe

Answer 7

13.7 billion years

Question 8

Depth of the Earth’s ocean

Answer 8

4 km

Question 9

Percent of Earth’s surface covered by ocean

Answer 9

70%

Question 10

Thickness of the Earth’s atmosphere

Answer 10

80 km

Question 11

Age of the Earth

Answer 11

4.6 billion years

Question 12

First evidence of life on Earth

Answer 12

3-4 billion years

Question 13

First evidence of multi-celled organisms

Answer 13

1 billion years

Question 14

Life first colonizes land

Answer 14

400 million years

Question 15

First mammals

Answer 15

225 million years

Question 16

Extinction of Dinosaurs (except for birds)

Answer 16

65 million years

Question 17

First hominids

Answer 17

5 million years

Question 18

First modern humans

Answer 18

200,000 years

Question 19

Date of first human civilization

Answer 19

8000 BC

Question 20

Start of the industrial revolution

Answer 20

1760

Question 21

Human population at the start of the industrial revolution

Answer 21

1 billion people

Question 22

Current human population

Answer 22

8 billion people

Question 23

Current rate of human population growth

Answer 23

1%

Question 24

Population in the US

Answer 24

300 million people

Question 25

Total per capita power utilization in the US

Answer 25

12 kW

Question 26

Total per capita power utilization in the world

Answer 26

2 kW

Question 27

The fraction of total energy used for industrial, transportation, commercial and
residential purposes

Answer 27

25%

Question 28

The fraction of total energy derived from fossil fuel sources

Answer 28

85%

Question 29

The current EPR for fossil fuels

Answer 29

5-10

Question 30

The date that domestic oil utilization peaked in the US

Answer 30

1975

Question 31

The concentration of CO2 in the Earth’s atmosphere

Answer 31

400 ppm

Question 32

The residence time of CO2 in the Earth’s atmosphere

Answer 32

100 years

Question 33

The infrared emissivity of most non-metals

Answer 33

1

Question 34

The infrared emissivity of most metals

Answer 34

0.05

Question 35

The average rate of Earth’s plate motions

Answer 35

2 cm/year

Question 36

The average energy of a solar photon

Answer 36

1.4 eV

Question 37

The approximate efficiency of current single junction silicon solar cells

Answer 37

20%

Question 38

The density of air at sea level

Answer 38

1.2 kg/ m^3

Question 39

The thickness of the Earth’s troposphere

Answer 39

11 km

Question 40

The average speed of west-to-east jet stream winds

Answer 40

25 m/sec

Question 41

The maximum theoretical efficiency of a wind turbine

Answer 41

59%

Question 42

The rated power of a large wind turbine

Answer 42

1.5 kW

Question 43

The energy produced by burning dry biomass

Answer 43

20 MJ/kg

Question 44

The energy produced by burning liquid ethanol

Answer 44

31 MJ/kg

Question 45

The time of day of maximum electrical power demand

Answer 45

5 pm

Question 46

The magnitude of the daily average fluctuation in electrical power demand

Answer 46

+/- 25%

Question 47

The battery storage capacity of a typical electric car

Answer 47

30 kWh

Question 48

The energy released during the fission of one 235 U atom

Answer 48

200 MeV

Question 49

The “safe” annual radiation dose for humans

Answer 49

3 mili-Sievert

Question 50

The approximate half-life of the most radioactive components of nuclear waste

Answer 50

1000 years

Question 51

USA’s mode annual family income

Answer 51

$19,000

Question 52

The year that California will hopefully achieve 100% carbon-free electricity

Answer 52

2045