Solar radiation is incident on a planet, whose a uwz6yxlpa x434 s3(l(dqb/zsurface absorbs 65% of incident intensity. What is the albedo of the planeaw3z/y(lb(lx pzu 6qa43 x4 dst?

  The orders of energy transforbm4l9 osq. qn lbc4.knz4-k5 dmations in 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 pairs constitutes *ivfxa8lh(uau6fh vq yd ;f2a -*vq (;a renewable and non-renewable source of energy vuday*afvax -qh hfu *;8qv6(fi2l;(?

  Which of the following pairs constitutes a renewable and noyx7ls ogr6 e9*n-renewable source of enl6ro7 *esx9 gyergy?

  Which of the following is a non7mm39xgo va *a 8cgj9v-renewable energy resource?

  Which of the following energy resourcesaof4p3s (i/h p is non-renewable?

  The government of a medium sized city plans to)vnbm5jp7 l- yflb y26 replace coal power plants with photovoltaic cells to power the cif- b2m)yv76 lnbpjly5ty.
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 around the Sun is 8yl20yp1bnnq19 lz bjapproximately 30 times the orbital radius of earth. Estiy9y1bl8p1ln bqj02n zmate the solar constant of Neptune.

  The following three statements gio k.eleuu -,9wve possible reasons why the average intensity of sunlight incident on a solar panel during a day on earth is only a fract9kwlue o,.e- uion 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 power stations. E qnlh jj.//9iyme x :,gpv8nj;xamples of electricity generation that both involve energy transfer from thermavgn l 9jqmpjex;i,hyn /j8.:/l to electrical are

  The albedo at the poles ofj5 kict 3tse 9c+tbw(3 Earth during a particular day is 0.8. What is the value of the absorbed intensity if thetcek(i93j3+tc b5 tw s solar intensity is 700 $Wm^{−2}$?

  The sun radiates energy to the surfac35ml)vix+v8 kxict0q e of the earth. Some of this energy is scattered and the rest reaches the emqt)c0+vvi l5 8xix3karth'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 surface is 60n xa.ak cu)i6r7y fn300 $Wm^{−2}$. 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 b g- e0d+9ifgpuurns fuel with a specific 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 b) t7e(s73fb wubimpbbu87 )xiody
(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.