Energy, Power And Climate Change

Question 0

Width of the arrow is proportional to the energy it carries

Answer 0

Sankey diagram

Question 1

Flow of … Tends to equalise … And deprives us from the opportunity to do work

Answer 1

Thermal energy / temperature

Question 2

Electricity production takes place in

Answer 2

Electric generators

Question 3

A generator converts mechanical energy (rotational energy from coil) to

Answer 3

Electrical energy

Question 4

Finite sources such as fossil and nuclear fuels

Answer 4

Non renewable

Question 5

Include solar and tidal energy

Answer 5

Renewable sources

Question 6

The energy that can be obtained from a unit mass of the fuel

Answer 6

Energy density

Question 7

Relatively cheap, high power output, variety of uses but cause environmental problems

Answer 7

Fossil fuels

Question 8

Typical fuel for nuclear reactions; critical mass must be present to induce chain reaction

Answer 8

Uranium 235

Question 9

Slow neutrons down in nuclear reactions in order to avoid captured by fuel

Answer 9

Moderator

Question 10

Isotope that does not occur naturally, created when U238 is bombarded with neutrons from fission reaction

Answer 10

Plutonium 239

Question 11

Plasma from nuclear fusion reactions is magnetically contained in

Answer 11

Tokamak

Question 12

Has fewer radiation wastes

Answer 12

Fusion

Question 13

All bodies that are kept at some absolute (kelvin) temperature T radiate energy in the form of electromagnetic waves

Answer 13

Black body law

Question 14

Power radiated by a body is governed by the

Answer 14

Stefan-Boltzmann law

Question 15

Amount of energy per second (i.e power) radiated by a body depends on its surface area, absolute temperature, and the properties of the surface.

Answer 15

P = eoAT^4

Question 16

When the constant of emissivity e of the surface is 1, …. A theoretical body that is a perfect emitter

Answer 16

Black body

Question 17

Most energy is radiated at specific wavelengths, determined by …. Of the body. The higher the …., the shorter the wavelength

Answer 17

Temperature

Question 18

The relation between the temperature and the peak wavelength (of curve), the wavelength at which most of the energy is emitted, is given by

Answer 18

Wien’s law

Question 19

May be considered to radiate as a perfect emitter (i.e as a black body)

Answer 19

The sun

Question 20

Ratio of the power of radiation reflected or scattered from the body, to the total power incident on the body

Answer 20

Albedo

Question 21

Warming of the earth caused by infrared radiation emitted by the surface which is absorbed by various gases in the atmosphere and partially radiated towards the surface

Answer 21

Greenhouse effect

Question 22

Infrared photons travelling through these gases will be absorbed; which means that the molecules will be excited to higher energy levels

Answer 22

Water vapour, carbon dioxide, methane and nitrous oxide

Question 23

When melted will not result in change of sea level because of Archimedes’ fluid mechanics

Answer 23

Sea ice

Question 24

Fractional change in volume per unit temperature change

Answer 24

Coefficient of volume expansion