Solar radiation is incident on a planet, whose surface absorbs 65% of incidenbn/:h; hpfhk*t intensity. What isf*bnphk:;h h/ the albedo of the planet?

  The orders of energy transformations in t3asm 4i in6o5pgrn5 a/hree 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 pairsn3x5bd,g 6p fbu 0js65)f/ ocs)dr9pzpyaz z; constitutes a renewable and non-renewable source of esb)3/zz9p)pfc5nx0aurj 56;szy6fop ,b g dd nergy?

  Which of the following pairs constitutes a renewable and non-renewab :s*p(a4xj zqqll+(x vle source ofl:a4zx (q (*xsqvjp+ l energy?

  Which of the following is a non-renewable energy resource?xbb/aw1m+c4 h m j ag3/(nvfnq3z4 8lj

  Which of the following energy reso /i5jh* :5uqxvur+em wurces is non-renewable?

  The government of a medium sized city pd9ksm /eg zwdw 7wr1,p:oaij3tw8 *x(lans to replace coal power plants with photovoltaic cells to power the city.x:idw(do83tm gw/9zkae,*j 1sw r pw7
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 Neptuaa6;x7 q3urunpv (fuejsbv6i d hh3h22)*4nq ne's orbit around the Sun is approximately 30 times the orbital radiuqh2u4;h s(jnxqbv3 p6vaiaf3u 72un)6hedr*s of earth. Estimate the solar constant of Neptune.

  The following three statements give ptk;y 6 7hi,*iz i .qyvtogn;) s0*kvnhossible reasons why the average intensity of sunlight incident on a solar panel during a day on earth is only a fvqo 7z ki nt i*yy;g)h;v0hk*tis6n., raction 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. Examplepb)vo7pd1 8m7e-w gq40dbvhfs of electricity generation that both id fmdo7h)v 0q17 pbbg-w8p4venvolve energy transfer from thermal to electrical are

  The albedo at the poles of Earth during a par(yarq91icl0 3wjnus** s)xe rticular day is 0.8. What is the value of the absorbe1wn*y isusa3q*)x(0 c jlr e9rd intensity if the solar intensity is 700 $Wm^{−2}$?

  The sun radiates energy to the surface of the earnb ft-q8w8 a(3dz813uyua de f2k,tgg th. Some of this energy is scattered ande8u2uat38wfayzk ,- bdn(g8qdg3f1 t 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 intensiol+o5v5sn* x lty on the Earth's surface 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 wieis3*r8 -0 m cz.p8cb h2jeo5vud w*ddth 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 ofet y/ab+ (9kxq a body
(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.