Solar radiation is incident on a planet, whose surface absorbs 65% of izovk7 ; auu)25p pjc4vncident intensity. What is the albedo of the pv2jo4zupv7)ca; u p5klanet?

  The orders of energy transformations inksb1vx4-pst/g0 un;s three power stations are given;

I. chemical → thermal → kinetic → electrical
II. kinetic → kinetic → electrical
III. gravitational potential → kinetic → electrical
Which row correctly matches the type of power station with the energy transformations?

  Which of the following pai5e 5 kd:irwqz6rs constitutes a renewable and non-renewable source of ke5 rwzi:5d q6energy?

  Which of the following pairs constituq d65t ol1dd7ctes a renewable and non-renewable source ofddd7q 16t lco5 energy?

  Which of the following is a non- ea/906j .bcpaemot qm+b)9 arrenewable energy resource?

  Which of the following energy resourr;rx6xk 8ke it8hq: p *66utiwces is non-renewable?

  The government of a medium sized city pla s9m pv52frw34lez; rcns to replace coal power plants with phot rcf;s pew 24lr5zv39movoltaic cells to power the city.
The following data are available:
Total area available for photovoltaic cells = 62.6$km^2$
Maximum intensity of light incident on photovoltaic cells = $1.36\times10^3$ $Wm^{−2}$
Average efficiency of energy conversion in photovoltaic cells = 20 %
Hours of sunshine in one month = 150 hours
1.Explain why the government's choice to reduce its reliance on coal would be beneficial to the Earth's climate.
2.Outline, in terms of energy changes, how electrical energy is generated from coal.
3.Using the data given, calculate in $GJ$ the maximum expected energy generation for one month. $Electrical energy obtained$ =    $\times10^6\,GJ$

  The average radius of Neptune's orbit aroub96- kvm -fvsend the Sun is approximately 30 times the orbital rad9 vfb --6emskvius of earth. Estimate the solar constant of Neptune.

  The following three statements give possible reasons why the average i depa :6m+ieb qij1+5)kyr+fa ntensity oemida6:b k1yqf5++j e+)p ai rf sunlight incident on a solar panel during a day on earth is only a fraction of the solar constant.
I. Scattering of sunlight in the atmosphere
II. Rotation of the earth
III. The surface of the solar panel is not perpendicular to incident of sunlight
Which of the statements are correct?

  Several energy conversions occur in pow65z n+(f)fzexcg2ooj )t- ksx er stations. Examples of electricity generation that both invz6)z2-)n f+jf es5cg(oxtk xoolve energy transfer from thermal to electrical are

  The albedo at the poles of Earth during a particulakr/b5q8f 0aw .x axzf/r day is 0.8. What is the value of the absorbed intensity if the solar in.x5f a/z/f xrq0a8b kwtensity is 700 $Wm^{−2}$?

  The sun radiates energy to the surface of the earth. Some of this energy vf9d:6etxa7 se jf5q6( bw goo pf/oga3i(0 c-is scattered a wg o 7b3 5xoe(:aia6etfpf- /9v(0qo g6csdfjnd the rest reaches the earth's surface.



1.Differentiate between heat transfer methods: conduction, convection and thermal radiation.
2.At any given time, the power of the radiation of the sun absorbed by the earth's surface is $P$.
$P$is given by
$P\,=\,(1−α)SπR^2$
Where $α$ is the albedo of the earth’s surface.
(1)Show that the average intensity of radiation $I_{avg}$​ that is absorbed by the earth's surface is given by $I_{avg}$​=$\frac{(1−α)S}{4}$. ​
(2)Calculate the average intensity of the radiation that is absorbed by the earth's surface. The earth's albedo is 0.3. $I_{avg}$ =    $Wm^{-2}$
Some of the infrared radiation from the earth is absorbed and reradiated by the greenhouse gasses.
3.Explain this absorption and emission of radiation in terms of molecular energy levels.

  On a certain day, the solar intensity on the Earth's su zn-1;bj ho.*i9thlfqrface is 300 $Wm^{−2}$. Photovoltaic cells which have an efficiency of 20% are used to convert solar energy to electrical energy. What should be the minimum area of the photovoltaic cells to produce an output of 6.0 kW assuming that the incident light is normal to the surface of the panel?

  A natural gas plant burns fuel with a speci1oyrkfw4j8y-az o e:gw e+ 96dfic energy of 80$MJkg^{−1}$.
The rate of energy input of the natural gas is 1.6$GW$. What is the rate at which the fuel burns?

  1.(1)Define the albedo of a body yy3. ips) y6f08xoof b
(2)It was suggested that painting rocky mountain tops with a white chalk-based paint could help reduce the impact of global warming. In terms of albedo, explain why this could work.
2.(1)Given that the radius of the earth is $6.4\times10^6\,m$, show that at any given time, the total amount of energy incident on the earth's surface is approximately $1.8\times10^{17}\,J$ per second. P =    $\times10^{17}\,W$
(2)The average albedo of the Earth is 0.30. What is the rate at which the Earth absorbs energy from the sun?
(3)Using your answer from (b)(ii) and ignoring atmospheric effects, estimate the average temperature of the earth for which equilibrium would be established. Assume the earth's average emissivity is 0.80.T =    K
(4)Greenhouse gases in the atmosphere elevate the average temperature of the earth such that it is higher than the answer found in (b)(iii). Explain the mechanism by which this occurs.